HTMLMailer Component

Properties   Methods   Events   Config Settings   Errors  

The HTMLMailer Component is used to send HTML emails, including embedded images.

Syntax

nsoftware.IPWorksSSL.HTMLMailer

Remarks

The HTMLMailer Component supports both plaintext and Secure Sockets Layer/Transport Layer Security (SSL/TLS) connections (RFC 2487). When connecting over Secure Sockets Layer/Transport Layer Security (SSL/TLS) the SSLServerAuthentication event allows you to check the server identity and other security attributes. The SSLStatus event provides information about the SSL handshake. Additional SSL-related settings are also supported through the Config method.

The component sends a message (provided in MessageHTML and MessageText). The HTML message may contain references to images that are automatically embedded into the message.

The MessageHTML property contains the HTML version of the message. The corresponding plaintext version is provided in the MessageText property.

When MessageHTML is set, the component automatically computes a plaintext version of the text and puts it into MessageText. You may choose to override this default text with your own version.

The recipients are specified by the SendTo, Cc, and BCc properties, and the message subject by the Subject property.

Once all the appropriate properties have been set, call the Send method and your message will be sent to its intended recipient(s).

Other SMTP headers may be specified through the OtherHeaders property. Information about interaction with the server is provided by the PITrail event.

Property List


The following is the full list of the properties of the component with short descriptions. Click on the links for further details.

AttachmentsThis property contains paths of the files to attach to the message.
AuthMechanismThis property is used when connecting to the mail server.
BCcThis property includes a comma-separated list of addresses for blind carbon copies (optional).
CcThis property includes a comma-separated list of addresses for carbon copies (optional).
ConnectedWhether the component is connected.
DeliveryNotificationToThis property includes the email address to which to send a delivery notification.
FirewallA set of properties related to firewall access.
FromThis property includes the email address of the sender (required).
HTMLFileThis property includes the path to a local HTML file.
IdleThe current status of the component.
ImagesThis property includes the embedded images in the HTML message.
ImportanceThis property indicates the importance of the mail message (optional).
LastReplyThis property indicates the last reply received from the server.
LocalHostThe name of the local host or user-assigned IP interface through which connections are initiated or accepted.
MailPortThis property includes the server port for SMTP (default 25).
MailServerThis property includes the name or address of a mail server (mail relay).
MessageDateThis property includes the date of the mail message (optional).
MessageHTMLThis property includes the HTML version of the message.
MessageIdThis property includes the message identifier for the message.
MessageRecipientsThis property includes the collection of recipients of the message.
MessageTextThis property includes the plaintext version of the message.
OtherHeadersThis property includes an RFC 822-compliant string consisting of extra headers.
ParseHTMLThis property controls the behavior of the MessageHTML property.
PasswordThis property includes a password for logon to the MailServer .
PriorityThis property includes the priority of the mail message (optional).
ReadReceiptToThis property includes the email address to send a read-receipt to.
ReplyToThis property includes a mail address to which to reply (optional).
SendToThis property includes a comma-separated list of addresses for destinations (required).
SensitivityThis property indicates the sensitivity of the mail message (optional).
SSLAcceptServerCertInstructs the component to unconditionally accept the server certificate that matches the supplied certificate.
SSLCertThe certificate to be used during Secure Sockets Layer (SSL) negotiation.
SSLProviderThe Secure Sockets Layer/Transport Layer Security (SSL/TLS) implementation to use.
SSLServerCertThe server certificate for the last established connection.
SSLStartModeThis property determines how the component starts the Secure Sockets Layer (SSL) negotiation.
SubjectThis property includes the subject of the mail message (optional).
TimeoutThe timeout for the component.
UserThis property includes the user identifier needed to log in as in the MailServer .

Method List


The following is the full list of the methods of the component with short descriptions. Click on the links for further details.

AddAttachmentThis adds FileName as an attachment.
CalcMessageTextThis method populates MessageText with the plaintext version of the message.
ConfigSets or retrieves a configuration setting.
ConnectThis method connects to the mail relay and sends the SMTP HELO command.
DisconnectThis method disconnects from the SMTP server.
DoEventsThis method processes events from the internal message queue.
InterruptThis method interrupts the current method.
ProcessQueueThis method sends the messages that previously have been queued into QueueDir .
QueueThis method queues the message into QueueDir .
ResetThis method will reset the component.
ResetHeadersThis method resets all the message headers to empty.
SendThis method sends the current message and MIME-encoded attachment.
SendCommandThis method sends the exact command directly to the server.
SetMessageHTMLStreamThis method sets the stream from which the component will read the HTML version of the message.

Event List


The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.

ConnectionStatusFired to indicate changes in the connection state.
EndTransferThis event is fired when the message text completes transferring.
ErrorFired when information is available about errors during data delivery.
PITrailThis event traces the commands sent to the mail server, and the respective replies.
SSLServerAuthenticationFired after the server presents its certificate to the client.
SSLStatusFired when secure connection progress messages are available.
StartTransferThis event is fired when the message text starts transferring.
TransferThis event is fired when the message text is transferred to MailServer .

Config Settings


The following is a list of config settings for the component with short descriptions. Click on the links for further details.

AttachmentEncoding[index]Content-Transfer-Encoding for attached file (at index).
AttachmentType[index]Content-type for attached file (at index).
CharsetWhen set, the charset Content-Type attribute will be added using the specified value.
ExcludeTagsSpecifies tags that will be excluded when calculating MessageText.
MessageTextEncodingWhen set, the MessageHTML and MessageText values will be encoded using the specified encoding.
OverrideFileNameIf set to true, the AttachmentName property value will be used to set the MIME part FileName attribute.
TempFilePathIf set, the temporary files created during message creation will be put in the path specified.
UseTempFileDetermines if temporary files are used during message creation.
AllowEmptyToIf set to True, then the SendTo property is not required.
AuthorizationIdentityThe value to use as the authorization identity when SASL authentication is used.
CharsetWhen set, the message headers will be encoded using the specified Charset.
FoldHeadersTells the component whether to fold the headers.
HelloThe argument for HELO (herald) command to the server (defaults to local host name).
KeepQueueIf set to True, queued files are not deleted after a successful send.
MaxHeaderLengthMaximum length for headers to avoid line folding (default 80).
MessageHeadersStringString representation of RFC822-encoded headers of the message.
MessageIdAlgorithmDetermines the algorithm used to hash the random MessageId.
OtherHeadersAn RFC 822 compliant string consisting of extra headers.
ReturnPathSets the Return-Path to be used for sending email.
SendRSETWhether to send RSET command.
StopOnBccErrorsInstructs the component to stop sending the message if the server does not acknowledge any of the BCCs.
StopOnCcErrorsInstructs the component to stop sending the message if the server does not acknowledge any of the CCs.
StopOnToErrorsInstructs the component to stop sending the message if the server does not acknowledge any of the TOs.
TransferTextString representation of RFC822-encoded body of the message.
CloseStreamAfterTransferIf true, the component will close the upload or download stream after the transfer.
ConnectionTimeoutSets a separate timeout value for establishing a connection.
FirewallAutoDetectTells the component whether or not to automatically detect and use firewall system settings, if available.
FirewallHostName or IP address of firewall (optional).
FirewallListenerIf true, the component binds to a SOCKS firewall as a server (TCPClient only).
FirewallPasswordPassword to be used if authentication is to be used when connecting through the firewall.
FirewallPortThe TCP port for the FirewallHost;.
FirewallTypeDetermines the type of firewall to connect through.
FirewallUserA user name if authentication is to be used connecting through a firewall.
KeepAliveIntervalThe retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.
KeepAliveTimeThe inactivity time in milliseconds before a TCP keep-alive packet is sent.
LingerWhen set to True, connections are terminated gracefully.
LingerTimeTime in seconds to have the connection linger.
LocalHostThe name of the local host through which connections are initiated or accepted.
LocalPortThe port in the local host where the component binds.
MaxLineLengthThe maximum amount of data to accumulate when no EOL is found.
MaxTransferRateThe transfer rate limit in bytes per second.
ProxyExceptionsListA semicolon separated list of hosts and IPs to bypass when using a proxy.
TCPKeepAliveDetermines whether or not the keep alive socket option is enabled.
TcpNoDelayWhether or not to delay when sending packets.
UseIPv6Whether to use IPv6.
UseNTLMv2Whether to use NTLM V2.
CACertFilePathsThe paths to CA certificate files when using Mono on Unix/Linux.
LogSSLPacketsControls whether SSL packets are logged when using the internal security API.
ReuseSSLSessionDetermines if the SSL session is reused.
SSLCACertsA newline separated list of CA certificates to be included when performing an SSL handshake.
SSLCheckCRLWhether to check the Certificate Revocation List for the server certificate.
SSLCheckOCSPWhether to use OCSP to check the status of the server certificate.
SSLCipherStrengthThe minimum cipher strength used for bulk encryption.
SSLClientCACertsA newline separated list of CA certificates to use during SSL client certificate validation.
SSLEnabledCipherSuitesThe cipher suite to be used in an SSL negotiation.
SSLEnabledProtocolsUsed to enable/disable the supported security protocols.
SSLEnableRenegotiationWhether the renegotiation_info SSL extension is supported.
SSLIncludeCertChainWhether the entire certificate chain is included in the SSLServerAuthentication event.
SSLKeyLogFileThe location of a file where per-session secrets are written for debugging purposes.
SSLNegotiatedCipherReturns the negotiated cipher suite.
SSLNegotiatedCipherStrengthReturns the negotiated cipher suite strength.
SSLNegotiatedCipherSuiteReturns the negotiated cipher suite.
SSLNegotiatedKeyExchangeReturns the negotiated key exchange algorithm.
SSLNegotiatedKeyExchangeStrengthReturns the negotiated key exchange algorithm strength.
SSLNegotiatedVersionReturns the negotiated protocol version.
SSLSecurityFlagsFlags that control certificate verification.
SSLServerCACertsA newline separated list of CA certificates to use during SSL server certificate validation.
TLS12SignatureAlgorithmsDefines the allowed TLS 1.2 signature algorithms when SSLProvider is set to Internal.
TLS12SupportedGroupsThe supported groups for ECC.
TLS13KeyShareGroupsThe groups for which to pregenerate key shares.
TLS13SignatureAlgorithmsThe allowed certificate signature algorithms.
TLS13SupportedGroupsThe supported groups for (EC)DHE key exchange.
AbsoluteTimeoutDetermines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallDataUsed to send extra data to the firewall.
InBufferSizeThe size in bytes of the incoming queue of the socket.
OutBufferSizeThe size in bytes of the outgoing queue of the socket.
BuildInfoInformation about the product's build.
GUIAvailableWhether or not a message loop is available for processing events.
LicenseInfoInformation about the current license.
MaskSensitiveDataWhether sensitive data is masked in log messages.
UseFIPSCompliantAPITells the component whether or not to use FIPS certified APIs.
UseInternalSecurityAPIWhether or not to use the system security libraries or an internal implementation.

Attachments Property (HTMLMailer Component)

This property contains paths of the files to attach to the message.

Syntax

public FileAttachmentList Attachments { get; }
Public Property Attachments As FileAttachmentList

Remarks

This property contains the path of a file on your system to be sent as an attachment with your message. The component will open the file and encode its contents in MIME format.

Example 1: Adding an Attachment

component.AddAttachment("C:\file1.zip"); component.AddAttachment("C:\file2.zip"); component.Send(); Example 2: Using an Attachments Collection

component.Attachments.Add(new nsoftware.IPWorks.FileAttachment("name", "C:\file.txt"));

This collection is indexed from 0 to count -1.

This property is not available at design time.

Please refer to the FileAttachment type for a complete list of fields.

AuthMechanism Property (HTMLMailer Component)

This property is used when connecting to the mail server.

Syntax

public HTMLMailerAuthMechanisms AuthMechanism { get; set; }

enum HTMLMailerAuthMechanisms { amUserPassword, amCRAMMD5, amNTLM, amAPOP, amSASLPlain, amSASLDigestMD5, amKerberos, amXOAUTH2 }
Public Property AuthMechanism As HtmlmailerAuthMechanisms

Enum HTMLMailerAuthMechanisms amUserPassword amCRAMMD5 amNTLM amAPOP amSASLPlain amSASLDigestMD5 amKerberos amXOAUTH2 End Enum

Default Value

0

Remarks

This is the authentication mechanism property to be used when connecting to the mail server.

By default, this property is amUserPassword (0), and if the User and Password properties are set, the AUTH command is sent to the server for authentication. If this property is set to amCRAMMD5 (1), CRAM-MD5 authentication is used instead.

If this property is set to amNTLM (2), NTLM authentication will be used.

If this property is set to amKerberos (6), Kerberos authentication will be used.

Note: This functionality is available only in Windows.

When set to amXOAUTH2 (7), set User to the username and AuthorizationIdentity to the OAuth token. See AuthorizationIdentity for details.

BCc Property (HTMLMailer Component)

This property includes a comma-separated list of addresses for blind carbon copies (optional).

Syntax

public string BCc { get; set; }
Public Property BCc As String

Default Value

""

Remarks

This property specifies a comma-separated list of destinations for blind carbon copies of the mail message. A copy of the message is sent to each destination. Because no BCc SMTP header is created containing the destination addresses, individual recipients never see the list of the other recipients.

The component will return an error if the MailServer returns an error code about any email address specified in SendTo or Cc but it will fire an Error event only if the same thing happens with an email address specified in this property.

If the resulting header is longer than MaxHeaderLength, then it is folded according to RFC 822 specifications.

Note: You must clear the MessageRecipients collection before setting this property to remove previous recipients.

Cc Property (HTMLMailer Component)

This property includes a comma-separated list of addresses for carbon copies (optional).

Syntax

public string Cc { get; set; }
Public Property Cc As String

Default Value

""

Remarks

This property specifies a comma-separated list of destinations for carbon copies of the mail message. A copy of the message is sent to each destination, and a Cc SMTP header is created containing the destination addresses. This header is sent to every recipient of the message. If you don't want to copy this information to every recipient, then use blind carbon copies instead (see the description of the BCc).

The component will return an error if the MailServer returns an error code about any email address specified in SendTo or Cc but it will fire an Error event only if the same thing happens with an email address specified in BCc.

If the resulting header is longer than MaxHeaderLength, then it is folded according to RFC 822 specifications.

Note: You must clear the MessageRecipients collection before setting this property to remove previous recipients.

Connected Property (HTMLMailer Component)

Whether the component is connected.

Syntax

public bool Connected { get; }
Public ReadOnly Property Connected As Boolean

Default Value

False

Remarks

This property is used to determine whether or not the component is connected to the remote host. Use the Connect and Disconnect methods to manage the connection.

This property is read-only and not available at design time.

DeliveryNotificationTo Property (HTMLMailer Component)

This property includes the email address to which to send a delivery notification.

Syntax

public string DeliveryNotificationTo { get; set; }
Public Property DeliveryNotificationTo As String

Default Value

""

Remarks

This property contains the email address to send to which to send a delivery notification. When set, a Return-Receipt-To header is added to the message. This property should be set to an email address that can receive the delivery notification.

Firewall Property (HTMLMailer Component)

A set of properties related to firewall access.

Syntax

public Firewall Firewall { get; set; }
Public Property Firewall As Firewall

Remarks

This is a Firewall-type property, which contains fields describing the firewall through which the component will attempt to connect.

Please refer to the Firewall type for a complete list of fields.

From Property (HTMLMailer Component)

This property includes the email address of the sender (required).

Syntax

public string From { get; set; }
Public Property From As String

Default Value

""

Remarks

This property is used to create a From SMTP header. This header identifies the sender of the message. A valid email address is required. Examples of valid addresses are as follows: "Friendly Name" <address@company.com> or address@company.com

If the resulting header is longer than MaxHeaderLength, then it is folded according to RFC 822 specifications.

HTMLFile Property (HTMLMailer Component)

This property includes the path to a local HTML file.

Syntax

public string HTMLFile { get; set; }
Public Property HTMLFile As String

Default Value

""

Remarks

This property may contain the path to the local HTML file. If this property is not empty, the contents of the file with that name will be appended to the text in MessageHTML.

Note: This means that if MessageHTML is empty, HTMLFile is what will be sent to the server.

This property is not available at design time.

Idle Property (HTMLMailer Component)

The current status of the component.

Syntax

public bool Idle { get; }
Public ReadOnly Property Idle As Boolean

Default Value

True

Remarks

This property will be False if the component is currently busy (communicating or waiting for an answer), and True at all other times.

This property is read-only.

Images Property (HTMLMailer Component)

This property includes the embedded images in the HTML message.

Syntax

public HTMLImageList Images { get; }
Public Property Images As HTMLImageList

Remarks

This property contains the names of the image files embedded into the HTML message. The collection is updated every time MessageHTML is set. You may change the file names before sending (e.g., if they don't point to valid files).

This collection is indexed from 0 to count -1.

Please refer to the HTMLImage type for a complete list of fields.

Importance Property (HTMLMailer Component)

This property indicates the importance of the mail message (optional).

Syntax

public HTMLMailerImportances Importance { get; set; }

enum HTMLMailerImportances { miUnspecified, miHigh, miNormal, miLow }
Public Property Importance As HtmlmailerImportances

Enum HTMLMailerImportances miUnspecified miHigh miNormal miLow End Enum

Default Value

0

Remarks

This property indicates the importance of the mail message (optional). When set, an Importance header will be added to the message.

Importance is an indication to the recipient(s) about the level of importance of the message. The possible values are Unspecified (0), High (1), Normal (2), and Low (3).

LastReply Property (HTMLMailer Component)

This property indicates the last reply received from the server.

Syntax

public string LastReply { get; }
Public ReadOnly Property LastReply As String

Default Value

""

Remarks

This property indicates the last reply received from the server. It can be used for informational purposes. The same information and more also can be retrieved through the PITrail event.

This property is read-only.

LocalHost Property (HTMLMailer Component)

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax

public string LocalHost { get; set; }
Public Property LocalHost As String

Default Value

""

Remarks

This property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multihomed hosts (machines with more than one IP interface) setting LocalHost to the IP address of an interface will make the component initiate connections (or accept in the case of server components) only through that interface. It is recommended to provide an IP address rather than a hostname when setting this property to ensure the desired interface is used.

If the component is connected, the LocalHost property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multihomed hosts (machines with more than one IP interface).

Note: LocalHost is not persistent. You must always set it in code, and never in the property window.

MailPort Property (HTMLMailer Component)

This property includes the server port for SMTP (default 25).

Syntax

public int MailPort { get; set; }
Public Property MailPort As Integer

Default Value

25

Remarks

This property contains the server port for SMTP (default 25). A valid port number (a value between 1 and 65535) is required for the connection to take place. The property must be set before a connection is attempted and cannot be changed once a connection is established. Any attempt to change this property while connected will fail with an error.

For an implicit Secure Sockets Layer (SSL), use port 465 (please refer to the SSLStartMode property for more information).

This property is not available at design time.

MailServer Property (HTMLMailer Component)

This property includes the name or address of a mail server (mail relay).

Syntax

public string MailServer { get; set; }
Public Property MailServer As String

Default Value

""

Remarks

This property specifies the IP address (IP number in dotted internet format) or domain name for a mail relay through which messages will be routed. It is set before a connection is attempted and cannot be changed once a connection is in progress.

The current version of the component does not provide a default value for the mail relay. You must provide a host name yourself. Generally, any internet host with an SMTP server will suffice (e.g., a UNIX host), but it is preferable to select a MailServer that is close to the machine sending mail.

If this property is set to a domain name, a DNS request is initiated. Upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, an error is returned.

If the component is configured to use a SOCKS firewall, the value assigned to this property may be preceded with an "*". If this is the case, the host name is passed to the firewall unresolved and the firewall performs the DNS resolution.

MessageDate Property (HTMLMailer Component)

This property includes the date of the mail message (optional).

Syntax

public string MessageDate { get; set; }
Public Property MessageDate As String

Default Value

"*"

Remarks

If this property contains a nonempty string, then a Date SMTP header is created and attached to the message. If it is an empty string, then the date information is added by the mail relay(s) the message goes through.

Special case: If this property is set to the special value "*", a Date SMTP header reflecting the current date and time is generated when MessageHeaders is computed and the message is sent. This is the default behavior of the component

RFC 822 contains detailed date format specifications. An example of a valid date is "Fri, 1 Mar 96 21:24:52 EST".

This property is not available at design time.

MessageHTML Property (HTMLMailer Component)

This property includes the HTML version of the message.

Syntax

public string MessageHTML { get; set; }
Public Property MessageHTML As String

Default Value

""

Remarks

This property contains the HTML version of the message.

When this property is set, the component automatically computes a plaintext version of the text and puts it into MessageText. You may choose to override this default text with your own version.

Example. Setting MessageHTML:

component.MessageHTML = "<b>Hello</b>, my name is <i>Tom</i>";

MessageId Property (HTMLMailer Component)

This property includes the message identifier for the message.

Syntax

public string MessageId { get; set; }
Public Property MessageId As String

Default Value

"*"

Remarks

This property contains the message identifier for the message. When set, the value of MessageId is used as the Message-Id header value of the message. A special value of "*" will automatically generate a random unique identifier for the message.

This property is not available at design time.

MessageRecipients Property (HTMLMailer Component)

This property includes the collection of recipients of the message.

Syntax

public MessageRecipientList MessageRecipients { get; }
Public Property MessageRecipients As MessageRecipientList

Remarks

This property contains a collection that describes to whom the message is being sent. You may include all recipients in this property, even Cc's and BCc's, which are specified by the type field.

This collection is indexed from 0 to count -1.

Please refer to the MessageRecipient type for a complete list of fields.

MessageText Property (HTMLMailer Component)

This property includes the plaintext version of the message.

Syntax

public string MessageText { get; set; }
Public Property MessageText As String

Default Value

""

Remarks

This property is a plaintext version of the HTML message. This is necessary for recipients with legacy mail readers that do not support HTML.

The MessageHTML property contains the HTML version of the message. When MessageHTML is set, the component automatically computes a plaintext version of the text and puts it into this property. You may choose to override this default text with your own version.

OtherHeaders Property (HTMLMailer Component)

This property includes an RFC 822-compliant string consisting of extra headers.

Syntax

public string OtherHeaders { get; set; }
Public Property OtherHeaders As String

Default Value

""

Remarks

This property contains a string of headers to be appended to the message headers created from other properties like SendTo, Subject, and so on.

The headers must be of the format "header: value" as specified in RFC 822. Header lines should be separated by CRLF ("\r\n") .

Use this property with caution. If this property contains invalid headers, message delivery might not be successful.

This property is useful for extending the functionality of the component. A good example is delivery of MIME-encoded messages.

Special case: If this property starts with an empty line (CRLF), then the value of this property is used instead of the normally computed message headers.

Example. Sending an Email with an Additional Header:

component.MailServer = "MyServer"; component.From = "me@server.com"; component.SendTo = "recipient@server.com"; component.Subject = "My Subject"; component.MessageText = "This is the message body."; component.OtherHeaders = "HeaderName: HeaderValue"; component.Send();

This property is not available at design time.

ParseHTML Property (HTMLMailer Component)

This property controls the behavior of the MessageHTML property.

Syntax

public bool ParseHTML { get; set; }
Public Property ParseHTML As Boolean

Default Value

True

Remarks

This property controls the behavior of the MessageHTML property. If ParseHTML is set to False, you must provide valid values in MessageHTML, MessageText, and Images.

Password Property (HTMLMailer Component)

This property includes a password for logon to the MailServer .

Syntax

public string Password { get; set; }
Public Property Password As String

Default Value

""

Remarks

If this property is set to a nonempty string, then when connecting to the MailServer an AUTH or CRAM-MD5 (depending on the value of AuthMechanism) command is sent to provide authentication information for the user.

This property is not available at design time.

Priority Property (HTMLMailer Component)

This property includes the priority of the mail message (optional).

Syntax

public HTMLMailerPriorities Priority { get; set; }

enum HTMLMailerPriorities { epUnspecified, epNormal, epUrgent, epNonUrgent }
Public Property Priority As HtmlmailerPriorities

Enum HTMLMailerPriorities epUnspecified epNormal epUrgent epNonUrgent End Enum

Default Value

0

Remarks

When this property is set, a priority header will be added to the message. Priority is an indication about the delivery priority of the message. The possible values are epNormal, epUrgent, and epNonUrgent.

ReadReceiptTo Property (HTMLMailer Component)

This property includes the email address to send a read-receipt to.

Syntax

public string ReadReceiptTo { get; set; }
Public Property ReadReceiptTo As String

Default Value

""

Remarks

When this property is set, a Disposition-Notification-To header is added to the message. This property should be set to an email address that should receive the read-receipt.

ReplyTo Property (HTMLMailer Component)

This property includes a mail address to which to reply (optional).

Syntax

public string ReplyTo { get; set; }
Public Property ReplyTo As String

Default Value

""

Remarks

If this property contains a nonempty string, a Reply-To SMTP header is created for the message. This header shows the address to use for replies, which is useful if this address is different from the one in From.

If the resulting header is longer than MaxHeaderLength, then it is folded according to RFC 822 specifications.

SendTo Property (HTMLMailer Component)

This property includes a comma-separated list of addresses for destinations (required).

Syntax

public string SendTo { get; set; }
Public Property SendTo As String

Default Value

""

Remarks

This property specifies a comma-separated list of destinations for the mail message. A copy of the message is sent to each of them, and a To SMTP header is created containing the destination addresses.

Examples of valid addresses are as follows: "Friendly Name" <address@company.com> or address@company.com

The component will fail if the MailServer returns an error code about any email address specified in SendTo or Cc but it will silently ignore the error if the same thing happens with an email address specified in BCc.

If the resulting header is longer than MaxHeaderLength, then it is folded according to RFC 822 specifications.

Note: You must clear the MessageRecipients collection before setting this property to remove previous recipients.

Sensitivity Property (HTMLMailer Component)

This property indicates the sensitivity of the mail message (optional).

Syntax

public HTMLMailerSensitivities Sensitivity { get; set; }

enum HTMLMailerSensitivities { esUnspecified, esPersonal, esPrivate, esCompanyConfidential }
Public Property Sensitivity As HtmlmailerSensitivities

Enum HTMLMailerSensitivities esUnspecified esPersonal esPrivate esCompanyConfidential End Enum

Default Value

0

Remarks

This property provides an indication of how sensitive it is to disclose the message to people other than the recipients of the message. When set, a Sensitivity header will added to the message. Possible values are as follows: esPersonal (1), esPrivate (2), and esCompanyConfidential (3).

SSLAcceptServerCert Property (HTMLMailer Component)

Instructs the component to unconditionally accept the server certificate that matches the supplied certificate.

Syntax

public Certificate SSLAcceptServerCert { get; set; }
Public Property SSLAcceptServerCert As Certificate

Remarks

If it finds any issues with the certificate presented by the server, the component will normally terminate the connection with an error.

You may override this behavior by supplying a value for SSLAcceptServerCert. If the certificate supplied in SSLAcceptServerCert is the same as the certificate presented by the server, then the server certificate is accepted unconditionally, and the connection will continue normally.

Note: This functionality is provided only for cases in which you otherwise know that you are communicating with the right server. If used improperly, this property may create a security breach. Use it at your own risk.

Please refer to the Certificate type for a complete list of fields.

SSLCert Property (HTMLMailer Component)

The certificate to be used during Secure Sockets Layer (SSL) negotiation.

Syntax

public Certificate SSLCert { get; set; }
Public Property SSLCert As Certificate

Remarks

This property includes the digital certificate that the component will use during SSL negotiation. Set this property to a valid certificate before starting SSL negotiation. To set a certificate, you may set the Encoded field to the encoded certificate. To select a certificate, use the store and subject fields.

Please refer to the Certificate type for a complete list of fields.

SSLProvider Property (HTMLMailer Component)

The Secure Sockets Layer/Transport Layer Security (SSL/TLS) implementation to use.

Syntax

public HTMLMailerSSLProviders SSLProvider { get; set; }

enum HTMLMailerSSLProviders { sslpAutomatic, sslpPlatform, sslpInternal }
Public Property SSLProvider As HtmlmailerSSLProviders

Enum HTMLMailerSSLProviders sslpAutomatic sslpPlatform sslpInternal End Enum

Default Value

0

Remarks

This property specifies the SSL/TLS implementation to use. In most cases the default value of 0 (Automatic) is recommended and should not be changed. When set to 0 (Automatic), the component will select whether to use the platform implementation or the internal implementation depending on the operating system as well as the TLS version being used.

Possible values are as follows:

0 (sslpAutomatic - default)Automatically selects the appropriate implementation.
1 (sslpPlatform) Uses the platform/system implementation.
2 (sslpInternal) Uses the internal implementation.
Additional Notes

In most cases using the default value (Automatic) is recommended. The component will select a provider depending on the current platform.

When Automatic is selected, on Windows, the component will use the platform implementation. On Linux/macOS, the component will use the internal implementation. When TLS 1.3 is enabled via SSLEnabledProtocols, the internal implementation is used on all platforms.

The .NET Standard library will always use the internal implementation on all platforms.

SSLServerCert Property (HTMLMailer Component)

The server certificate for the last established connection.

Syntax

public Certificate SSLServerCert { get; }
Public ReadOnly Property SSLServerCert As Certificate

Remarks

This property contains the server certificate for the last established connection.

SSLServerCert is reset every time a new connection is attempted.

This property is read-only.

Please refer to the Certificate type for a complete list of fields.

SSLStartMode Property (HTMLMailer Component)

This property determines how the component starts the Secure Sockets Layer (SSL) negotiation.

Syntax

public HTMLMailerSSLStartModes SSLStartMode { get; set; }

enum HTMLMailerSSLStartModes { sslAutomatic, sslImplicit, sslExplicit }
Public Property SSLStartMode As HtmlmailerSSLStartModes

Enum HTMLMailerSSLStartModes sslAutomatic sslImplicit sslExplicit End Enum

Default Value

0

Remarks

The SSLStartMode property may have one of the following values:

0 (sslAutomatic)If the remote port is set to the standard plaintext port of the protocol (where applicable), the component will behave the same as if SSLStartMode is set to sslExplicit. In all other cases, SSL negotiation will be implicit (sslImplicit).
1 (sslImplicit)The SSL negotiation will start immediately after the connection is established.
2 (sslExplicit)The component will first connect in plaintext, and then will explicitly start SSL negotiation through a protocol command such as STARTTLS.

Subject Property (HTMLMailer Component)

This property includes the subject of the mail message (optional).

Syntax

public string Subject { get; set; }
Public Property Subject As String

Default Value

""

Remarks

The string in this property is sent with a Subject SMTP header to the mail recipient.

If the resulting header is longer than MaxHeaderLength, then it is folded according to RFC 822 specifications.

Timeout Property (HTMLMailer Component)

The timeout for the component.

Syntax

public int Timeout { get; set; }
Public Property Timeout As Integer

Default Value

60

Remarks

If the Timeout property is set to 0, all operations will run uninterrupted until successful completion or an error condition is encountered.

If Timeout is set to a positive value, the component will wait for the operation to complete before returning control.

The component will use DoEvents to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not freeze and remains responsive.

If Timeout expires, and the operation is not yet complete, the component throws an exception.

Note: By default, all timeouts are inactivity timeouts, that is, the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the Timeout property is 60 seconds.

User Property (HTMLMailer Component)

This property includes the user identifier needed to log in as in the MailServer .

Syntax

public string User { get; set; }
Public Property User As String

Default Value

""

Remarks

If this property is set to a nonempty string, then when connecting to the MailServer an AUTH or CRAM-MD5 (depending on the value of AuthMechanism) command is sent to provide authentication information for the user.

This property is not available at design time.

AddAttachment Method (HTMLMailer Component)

This adds FileName as an attachment.

Syntax

public void AddAttachment(string fileName);

Async Version
public async Task AddAttachment(string fileName);
public async Task AddAttachment(string fileName, CancellationToken cancellationToken);
Public Sub AddAttachment(ByVal FileName As String)

Async Version
Public Sub AddAttachment(ByVal FileName As String) As Task
Public Sub AddAttachment(ByVal FileName As String, cancellationToken As CancellationToken) As Task

Remarks

This method adds the file name as an attachment. The full list of attachments is contained in the Attachments property.

Example 1: Adding an Attachment

component.AddAttachment("C:\file1.zip"); component.AddAttachment("C:\file2.zip"); component.Send(); Example 2: Using an Attachments Collection

component.Attachments.Add(new nsoftware.IPWorks.FileAttachment("name", "C:\file.txt"));

CalcMessageText Method (HTMLMailer Component)

This method populates MessageText with the plaintext version of the message.

Syntax

public void CalcMessageText();

Async Version
public async Task CalcMessageText();
public async Task CalcMessageText(CancellationToken cancellationToken);
Public Sub CalcMessageText()

Async Version
Public Sub CalcMessageText() As Task
Public Sub CalcMessageText(cancellationToken As CancellationToken) As Task

Remarks

This method parses MessageHTML or HTMLFile and calculates a plaintext version of the message. The plaintext version is stored in the MessageText property.

Calling this method is optional. When the Send method is called, the component will automatically calculate a plaintext version of the message. This may be called in cases in which the plaintext version will be set explicitly. For instance:

component.MessageHTML="<html><body><b>Test Message</b></body></html>"; component.CalcMessageText(); component.MessageText = "A new custom plaintext message";

Config Method (HTMLMailer Component)

Sets or retrieves a configuration setting.

Syntax

public string Config(string configurationString);

Async Version
public async Task<string> Config(string configurationString);
public async Task<string> Config(string configurationString, CancellationToken cancellationToken);
Public Function Config(ByVal ConfigurationString As String) As String

Async Version
Public Function Config(ByVal ConfigurationString As String) As Task(Of String)
Public Function Config(ByVal ConfigurationString As String, cancellationToken As CancellationToken) As Task(Of String)

Remarks

Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

Connect Method (HTMLMailer Component)

This method connects to the mail relay and sends the SMTP HELO command.

Syntax

public void Connect();

Async Version
public async Task Connect();
public async Task Connect(CancellationToken cancellationToken);
Public Sub Connect()

Async Version
Public Sub Connect() As Task
Public Sub Connect(cancellationToken As CancellationToken) As Task

Remarks

This method connects to the mail relay and sends the SMTP HELO command, thus preparing to send messages. Any number of messages can later be sent using the Send method.

Example. Connecting and Sending an Email:

control.MailServer = "MyServer" control.From = "me@server.com" control.SendTo = "recipient@server.com" control.Subject = "My Subject" control.MessageText = "This is the message body" control.Connect() control.Send() control.Disconnect()

Disconnect Method (HTMLMailer Component)

This method disconnects from the SMTP server.

Syntax

public void Disconnect();

Async Version
public async Task Disconnect();
public async Task Disconnect(CancellationToken cancellationToken);
Public Sub Disconnect()

Async Version
Public Sub Disconnect() As Task
Public Sub Disconnect(cancellationToken As CancellationToken) As Task

Remarks

This method disconnects from the mail relay.

DoEvents Method (HTMLMailer Component)

This method processes events from the internal message queue.

Syntax

public void DoEvents();

Async Version
public async Task DoEvents();
public async Task DoEvents(CancellationToken cancellationToken);
Public Sub DoEvents()

Async Version
Public Sub DoEvents() As Task
Public Sub DoEvents(cancellationToken As CancellationToken) As Task

Remarks

When DoEvents is called, the component processes any available events. If no events are available, it waits for a preset period of time, and then returns.

Interrupt Method (HTMLMailer Component)

This method interrupts the current method.

Syntax

public void Interrupt();

Async Version
public async Task Interrupt();
public async Task Interrupt(CancellationToken cancellationToken);
Public Sub Interrupt()

Async Version
Public Sub Interrupt() As Task
Public Sub Interrupt(cancellationToken As CancellationToken) As Task

Remarks

If there is no method in progress, Interrupt simply returns, doing nothing.

ProcessQueue Method (HTMLMailer Component)

This method sends the messages that previously have been queued into QueueDir .

Syntax

public void ProcessQueue(string queueDir);

Async Version
public async Task ProcessQueue(string queueDir);
public async Task ProcessQueue(string queueDir, CancellationToken cancellationToken);
Public Sub ProcessQueue(ByVal QueueDir As String)

Async Version
Public Sub ProcessQueue(ByVal QueueDir As String) As Task
Public Sub ProcessQueue(ByVal QueueDir As String, cancellationToken As CancellationToken) As Task

Remarks

This method sends the messages that previously have been queued into QueueDir. The PITrail event shows the interaction with the server as messages are processed.

This method looks in the directory for files with the extension ".queued" and starts processing them.

When processing starts, the file extension is changed to ".sending". If an error happens at this stage, the sending process is aborted, and the file extension is changed to ".failed".

If the file is successfully sent, the file is normally deleted, unless the KeepQueue configuration setting is set to True, in which case the file extension is instead changed to ".sent" and the queue file is not deleted.

Queue Method (HTMLMailer Component)

This method queues the message into QueueDir .

Syntax

public string Queue(string queueDir);

Async Version
public async Task<string> Queue(string queueDir);
public async Task<string> Queue(string queueDir, CancellationToken cancellationToken);
Public Function Queue(ByVal QueueDir As String) As String

Async Version
Public Function Queue(ByVal QueueDir As String) As Task(Of String)
Public Function Queue(ByVal QueueDir As String, cancellationToken As CancellationToken) As Task(Of String)

Remarks

This method queues the message into QueueDir. The message is queued into a unique file into the directory QueueDir for future processing.

QueueDir must already exist, or an error will be generated. Alternatively, QueueDir may be set to "*" to return the result as a string instead of writing it to a file.

This method returns the name of the unique queue file created in QueueDir. The file extension is ".queued".

Please refer to the ProcessQueue method for more information on email queue processing.

Reset Method (HTMLMailer Component)

This method will reset the component.

Syntax

public void Reset();

Async Version
public async Task Reset();
public async Task Reset(CancellationToken cancellationToken);
Public Sub Reset()

Async Version
Public Sub Reset() As Task
Public Sub Reset(cancellationToken As CancellationToken) As Task

Remarks

This method will reset the component's properties to their default values.

ResetHeaders Method (HTMLMailer Component)

This method resets all the message headers to empty.

Syntax

public void ResetHeaders();

Async Version
public async Task ResetHeaders();
public async Task ResetHeaders(CancellationToken cancellationToken);
Public Sub ResetHeaders()

Async Version
Public Sub ResetHeaders() As Task
Public Sub ResetHeaders(cancellationToken As CancellationToken) As Task

Remarks

This method resets all the message headers to "" (empty string). Use this method before creating a new message, so that headers from the previous message are not carried over to the next one.

Send Method (HTMLMailer Component)

This method sends the current message and MIME-encoded attachment.

Syntax

public void Send();

Async Version
public async Task Send();
public async Task Send(CancellationToken cancellationToken);
Public Sub Send()

Async Version
Public Sub Send() As Task
Public Sub Send(cancellationToken As CancellationToken) As Task

Remarks

This method sends the current message and MIME-encoded attachment. If the component is not connected to the mail relay, a connection is created, the message is sent, and then the connection is closed unless an error occurs.

If the component is already connected (by use of the Connect method), the connection will remain open after the message is sent. To disconnect, call the Disconnect method.

Example. Send an HTML Email:

HTMLMailerControl.MailServer = "myserver" HTMLMailerControl.SendTo = "recipient@myserver.com" HTMLMailerControl.From = "me@myserver.com" HTMLMailerControl.Subject = "My Subject" HTMLMailerControl.MessageHTML = "<b>Hello</b>, my name is <i>Tom</i>" HTMLMailerControl.Send

SendCommand Method (HTMLMailer Component)

This method sends the exact command directly to the server.

Syntax

public void SendCommand(string command);

Async Version
public async Task SendCommand(string command);
public async Task SendCommand(string command, CancellationToken cancellationToken);
Public Sub SendCommand(ByVal Command As String)

Async Version
Public Sub SendCommand(ByVal Command As String) As Task
Public Sub SendCommand(ByVal Command As String, cancellationToken As CancellationToken) As Task

Remarks

This method sends the command specified by Command to the server exactly as it is provided. Use this method to send additional or custom commands directly to the server.

After calling this method, check the LastReply property or monitor the PITrail event to obtain the server's response.

SetMessageHTMLStream Method (HTMLMailer Component)

This method sets the stream from which the component will read the HTML version of the message.

Syntax

public void SetMessageHTMLStream(System.IO.Stream messageStream);

Async Version
public async Task SetMessageHTMLStream(System.IO.Stream messageStream);
public async Task SetMessageHTMLStream(System.IO.Stream messageStream, CancellationToken cancellationToken);
Public Sub SetMessageHTMLStream(ByVal MessageStream As System.IO.Stream)

Async Version
Public Sub SetMessageHTMLStream(ByVal MessageStream As System.IO.Stream) As Task
Public Sub SetMessageHTMLStream(ByVal MessageStream As System.IO.Stream, cancellationToken As CancellationToken) As Task

Remarks

This method sets the stream from which the component will read the HTML version of the message. Once set, the component reads the content of the stream and populates the MessageHTML property with the HTML version of the message. The corresponding plaintext version is provided in the MessageText property.

When this property is called, the component automatically computes a plaintext version of the text and puts it into MessageText. You may choose to override this default text with your own version.

ConnectionStatus Event (HTMLMailer Component)

Fired to indicate changes in the connection state.

Syntax

public event OnConnectionStatusHandler OnConnectionStatus;

public delegate void OnConnectionStatusHandler(object sender, HTMLMailerConnectionStatusEventArgs e);

public class HTMLMailerConnectionStatusEventArgs : EventArgs {
  public string ConnectionEvent { get; }
  public int StatusCode { get; }
  public string Description { get; }
}
Public Event OnConnectionStatus As OnConnectionStatusHandler

Public Delegate Sub OnConnectionStatusHandler(sender As Object, e As HTMLMailerConnectionStatusEventArgs)

Public Class HTMLMailerConnectionStatusEventArgs Inherits EventArgs
  Public ReadOnly Property ConnectionEvent As String
  Public ReadOnly Property StatusCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

This event is fired when the connection state changes: for example, completion of a firewall or proxy connection or completion of a security handshake.

The ConnectionEvent parameter indicates the type of connection event. Values may include the following:

Firewall connection complete.
Secure Sockets Layer (SSL) or S/Shell handshake complete (where applicable).
Remote host connection complete.
Remote host disconnected.
SSL or S/Shell connection broken.
Firewall host disconnected.
StatusCode has the error code returned by the Transmission Control Protocol (TCP)/IP stack. Description contains a description of this code. The value of StatusCode is equal to the value of the error.

EndTransfer Event (HTMLMailer Component)

This event is fired when the message text completes transferring.

Syntax

public event OnEndTransferHandler OnEndTransfer;

public delegate void OnEndTransferHandler(object sender, HTMLMailerEndTransferEventArgs e);

public class HTMLMailerEndTransferEventArgs : EventArgs {
  public int Direction { get; }
}
Public Event OnEndTransfer As OnEndTransferHandler

Public Delegate Sub OnEndTransferHandler(sender As Object, e As HTMLMailerEndTransferEventArgs)

Public Class HTMLMailerEndTransferEventArgs Inherits EventArgs
  Public ReadOnly Property Direction As Integer
End Class

Remarks

If MessageText is not empty, the EndTransfer event is fired when the MessageText finishes transferring from the local host to the MailServer. If MessageText is empty, the event is not fired.

If a file is attached to the MessageText via the AttachedFile property, then EndTransfer fires again when the file finishes transferring. For more information, go to the description of the AttachedFile property.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

Error Event (HTMLMailer Component)

Fired when information is available about errors during data delivery.

Syntax

public event OnErrorHandler OnError;

public delegate void OnErrorHandler(object sender, HTMLMailerErrorEventArgs e);

public class HTMLMailerErrorEventArgs : EventArgs {
  public int ErrorCode { get; }
  public string Description { get; }
}
Public Event OnError As OnErrorHandler

Public Delegate Sub OnErrorHandler(sender As Object, e As HTMLMailerErrorEventArgs)

Public Class HTMLMailerErrorEventArgs Inherits EventArgs
  Public ReadOnly Property ErrorCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component throws an exception.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

PITrail Event (HTMLMailer Component)

This event traces the commands sent to the mail server, and the respective replies.

Syntax

public event OnPITrailHandler OnPITrail;

public delegate void OnPITrailHandler(object sender, HTMLMailerPITrailEventArgs e);

public class HTMLMailerPITrailEventArgs : EventArgs {
  public int Direction { get; }
  public string Message { get; }
}
Public Event OnPITrail As OnPITrailHandler

Public Delegate Sub OnPITrailHandler(sender As Object, e As HTMLMailerPITrailEventArgs)

Public Class HTMLMailerPITrailEventArgs Inherits EventArgs
  Public ReadOnly Property Direction As Integer
  Public ReadOnly Property Message As String
End Class

Remarks

The PITrail event is useful for debugging purposes. It shows all of the interaction between the client and the server, line by line, except for message header and body transfers.

The Message parameter contains the full text of the message. The Direction parameter shows the originator of the message:

0 (Client)The Message originates from the client.
1 (Server)The Message originates from the server.
2 (Info)The Message is an informative message originating from the client software (the component code).

SSLServerAuthentication Event (HTMLMailer Component)

Fired after the server presents its certificate to the client.

Syntax

public event OnSSLServerAuthenticationHandler OnSSLServerAuthentication;

public delegate void OnSSLServerAuthenticationHandler(object sender, HTMLMailerSSLServerAuthenticationEventArgs e);

public class HTMLMailerSSLServerAuthenticationEventArgs : EventArgs {
  public string CertEncoded { get; }
public byte[] CertEncodedB { get; } public string CertSubject { get; } public string CertIssuer { get; } public string Status { get; } public bool Accept { get; set; } }
Public Event OnSSLServerAuthentication As OnSSLServerAuthenticationHandler

Public Delegate Sub OnSSLServerAuthenticationHandler(sender As Object, e As HTMLMailerSSLServerAuthenticationEventArgs)

Public Class HTMLMailerSSLServerAuthenticationEventArgs Inherits EventArgs
  Public ReadOnly Property CertEncoded As String
Public ReadOnly Property CertEncodedB As Byte() Public ReadOnly Property CertSubject As String Public ReadOnly Property CertIssuer As String Public ReadOnly Property Status As String Public Property Accept As Boolean End Class

Remarks

During this event, the client can decide whether or not to continue with the connection process. The Accept parameter is a recommendation on whether to continue or close the connection. This is just a suggestion: application software must use its own logic to determine whether or not to continue.

When Accept is False, Status shows why the verification failed (otherwise, Status contains the string OK). If it is decided to continue, you can override and accept the certificate by setting the Accept parameter to True.

SSLStatus Event (HTMLMailer Component)

Fired when secure connection progress messages are available.

Syntax

public event OnSSLStatusHandler OnSSLStatus;

public delegate void OnSSLStatusHandler(object sender, HTMLMailerSSLStatusEventArgs e);

public class HTMLMailerSSLStatusEventArgs : EventArgs {
  public string Message { get; }
}
Public Event OnSSLStatus As OnSSLStatusHandler

Public Delegate Sub OnSSLStatusHandler(sender As Object, e As HTMLMailerSSLStatusEventArgs)

Public Class HTMLMailerSSLStatusEventArgs Inherits EventArgs
  Public ReadOnly Property Message As String
End Class

Remarks

The event is fired for informational and logging purposes only. This event tracks the progress of the connection.

StartTransfer Event (HTMLMailer Component)

This event is fired when the message text starts transferring.

Syntax

public event OnStartTransferHandler OnStartTransfer;

public delegate void OnStartTransferHandler(object sender, HTMLMailerStartTransferEventArgs e);

public class HTMLMailerStartTransferEventArgs : EventArgs {
  public int Direction { get; }
}
Public Event OnStartTransfer As OnStartTransferHandler

Public Delegate Sub OnStartTransferHandler(sender As Object, e As HTMLMailerStartTransferEventArgs)

Public Class HTMLMailerStartTransferEventArgs Inherits EventArgs
  Public ReadOnly Property Direction As Integer
End Class

Remarks

If MessageText is not empty, the StartTransfer event is fired when the MessageText starts transferring from the local host to the MailServer. If MessageText is empty, the event is not fired.

If a file is attached to the MessageText via the AttachedFile property, then StartTransfer fires again when the file starts transferring. Please go to the description of the AttachedFile property for more information.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

Transfer Event (HTMLMailer Component)

This event is fired when the message text is transferred to MailServer .

Syntax

public event OnTransferHandler OnTransfer;

public delegate void OnTransferHandler(object sender, HTMLMailerTransferEventArgs e);

public class HTMLMailerTransferEventArgs : EventArgs {
  public int Direction { get; }
  public long BytesTransferred { get; }
  public int PercentDone { get; }
  public string Text { get; }
public byte[] TextB { get; } }
Public Event OnTransfer As OnTransferHandler

Public Delegate Sub OnTransferHandler(sender As Object, e As HTMLMailerTransferEventArgs)

Public Class HTMLMailerTransferEventArgs Inherits EventArgs
  Public ReadOnly Property Direction As Integer
  Public ReadOnly Property BytesTransferred As Long
  Public ReadOnly Property PercentDone As Integer
  Public ReadOnly Property Text As String
Public ReadOnly Property TextB As Byte() End Class

Remarks

One or more Transfer events are fired during message delivery. Messages consist of MessageText and an optional AttachedFile. The BytesTransferred parameter shows the number of bytes sent starting from the beginning of MessageText or AttachedFile.

Text contains the current portion of the message being sent.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

The PercentDone parameter shows the progress of the transfer in the corresponding direction. If PercentDone can not be calculated the value will be -1.

Note: Events are not re-entrant. Performing time-consuming operations within this event will prevent it from firing again in a timely manner and may affect overall performance.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

The following fields are available:

Fields

EffectiveDate
string (read-only)

Default: ""

The date on which this certificate becomes valid. Before this date, it is not valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2000 15:00:00.

ExpirationDate
string (read-only)

Default: ""

The date on which the certificate expires. After this date, the certificate will no longer be valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2001 15:00:00.

ExtendedKeyUsage
string (read-only)

Default: ""

A comma-delimited list of extended key usage identifiers. These are the same as ASN.1 object identifiers (OIDs).

Fingerprint
string (read-only)

Default: ""

The hex-encoded, 16-byte MD5 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: bc:2a:72:af:fe:58:17:43:7a:5f:ba:5a:7c:90:f7:02

FingerprintSHA1
string (read-only)

Default: ""

The hex-encoded, 20-byte SHA-1 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 30:7b:fa:38:65:83:ff:da:b4:4e:07:3f:17:b8:a4:ed:80:be:ff:84

FingerprintSHA256
string (read-only)

Default: ""

The hex-encoded, 32-byte SHA-256 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 6a:80:5c:33:a9:43:ea:b0:96:12:8a:64:96:30:ef:4a:8a:96:86:ce:f4:c7:be:10:24:8e:2b:60:9e:f3:59:53

Issuer
string (read-only)

Default: ""

The issuer of the certificate. This field contains a string representation of the name of the issuing authority for the certificate.

PrivateKey
string (read-only)

Default: ""

The private key of the certificate (if available). The key is provided as PEM/Base64-encoded data.

Note: The PrivateKey may be available but not exportable. In this case, PrivateKey returns an empty string.

PrivateKeyAvailable
bool (read-only)

Default: False

Whether a PrivateKey is available for the selected certificate. If PrivateKeyAvailable is True, the certificate may be used for authentication purposes (e.g., server authentication).

PrivateKeyContainer
string (read-only)

Default: ""

The name of the PrivateKey container for the certificate (if available). This functionality is available only on Windows platforms.

PublicKey
string (read-only)

Default: ""

The public key of the certificate. The key is provided as PEM/Base64-encoded data.

PublicKeyAlgorithm
string (read-only)

Default: ""

The textual description of the certificate's public key algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_DH") or an object identifier (OID) string representing the algorithm.

PublicKeyLength
int (read-only)

Default: 0

The length of the certificate's public key (in bits). Common values are 512, 1024, and 2048.

SerialNumber
string (read-only)

Default: ""

The serial number of the certificate encoded as a string. The number is encoded as a series of hexadecimal digits, with each pair representing a byte of the serial number.

SignatureAlgorithm
string (read-only)

Default: ""

The text description of the certificate's signature algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_MD5RSA") or an object identifier (OID) string representing the algorithm.

Store
string

Default: "MY"

The name of the certificate store for the client certificate.

The StoreType field denotes the type of the certificate store specified by Store. If the store is password-protected, specify the password in StorePassword.

Store is used in conjunction with the Subject field to specify client certificates. If Store has a value, and Subject or Encoded is set, a search for a certificate is initiated. Please see the Subject field for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

MYA certificate store holding personal certificates with their associated private keys.
CACertifying authority certificates.
ROOTRoot certificates.

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

StoreB
byte []

Default: "MY"

The name of the certificate store for the client certificate.

The StoreType field denotes the type of the certificate store specified by Store. If the store is password-protected, specify the password in StorePassword.

Store is used in conjunction with the Subject field to specify client certificates. If Store has a value, and Subject or Encoded is set, a search for a certificate is initiated. Please see the Subject field for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

MYA certificate store holding personal certificates with their associated private keys.
CACertifying authority certificates.
ROOTRoot certificates.

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

StorePassword
string

Default: ""

If the type of certificate store requires a password, this field is used to specify the password needed to open the certificate store.

StoreType
CertStoreTypes

Default: 0

The type of certificate store for this certificate.

The component supports both public and private keys in a variety of formats. When the cstAuto value is used, the component will automatically determine the type. This field can take one of the following values:

0 (cstUser - default)For Windows, this specifies that the certificate store is a certificate store owned by the current user.

Note: This store type is not available in Java.

1 (cstMachine)For Windows, this specifies that the certificate store is a machine store.

Note: This store type is not available in Java.

2 (cstPFXFile)The certificate store is the name of a PFX (PKCS#12) file containing certificates.
3 (cstPFXBlob)The certificate store is a string (binary or Base64-encoded) representing a certificate store in PFX (PKCS#12) format.
4 (cstJKSFile)The certificate store is the name of a Java Key Store (JKS) file containing certificates.

Note: This store type is only available in Java.

5 (cstJKSBlob)The certificate store is a string (binary or Base64-encoded) representing a certificate store in Java Key Store (JKS) format.

Note: This store type is only available in Java.

6 (cstPEMKeyFile)The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
7 (cstPEMKeyBlob)The certificate store is a string (binary or Base64-encoded) that contains a private key and an optional certificate.
8 (cstPublicKeyFile)The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
9 (cstPublicKeyBlob)The certificate store is a string (binary or Base64-encoded) that contains a PEM- or DER-encoded public key certificate.
10 (cstSSHPublicKeyBlob)The certificate store is a string (binary or Base64-encoded) that contains an SSH-style public key.
11 (cstP7BFile)The certificate store is the name of a PKCS#7 file containing certificates.
12 (cstP7BBlob)The certificate store is a string (binary) representing a certificate store in PKCS#7 format.
13 (cstSSHPublicKeyFile)The certificate store is the name of a file that contains an SSH-style public key.
14 (cstPPKFile)The certificate store is the name of a file that contains a PPK (PuTTY Private Key).
15 (cstPPKBlob)The certificate store is a string (binary) that contains a PPK (PuTTY Private Key).
16 (cstXMLFile)The certificate store is the name of a file that contains a certificate in XML format.
17 (cstXMLBlob)The certificate store is a string that contains a certificate in XML format.
18 (cstJWKFile)The certificate store is the name of a file that contains a JWK (JSON Web Key).
19 (cstJWKBlob)The certificate store is a string that contains a JWK (JSON Web Key).
21 (cstBCFKSFile)The certificate store is the name of a file that contains a BCFKS (Bouncy Castle FIPS Key Store).

Note: This store type is only available in Java and .NET.

22 (cstBCFKSBlob)The certificate store is a string (binary or Base64-encoded) representing a certificate store in BCFKS (Bouncy Castle FIPS Key Store) format.

Note: This store type is only available in Java and .NET.

23 (cstPKCS11)The certificate is present on a physical security key accessible via a PKCS#11 interface.

To use a security key, the necessary data must first be collected using the CertMgr component. The ListStoreCertificates method may be called after setting CertStoreType to cstPKCS11, CertStorePassword to the PIN, and CertStore to the full path of the PKCS#11 DLL. The certificate information returned in the CertList event's CertEncoded parameter may be saved for later use.

When using a certificate, pass the previously saved security key information as the Store and set StorePassword to the PIN.

Code Example. SSH Authentication with Security Key: certmgr.CertStoreType = CertStoreTypes.cstPKCS11; certmgr.OnCertList += (s, e) => { secKeyBlob = e.CertEncoded; }; certmgr.CertStore = @"C:\Program Files\OpenSC Project\OpenSC\pkcs11\opensc-pkcs11.dll"; certmgr.CertStorePassword = "123456"; //PIN certmgr.ListStoreCertificates(); sftp.SSHCert = new Certificate(CertStoreTypes.cstPKCS11, secKeyBlob, "123456", "*"); sftp.SSHUser = "test"; sftp.SSHLogon("myhost", 22);

99 (cstAuto)The store type is automatically detected from the input data. This setting may be used with both public and private keys and can detect any of the supported formats automatically.

SubjectAltNames
string (read-only)

Default: ""

Comma-separated lists of alternative subject names for the certificate.

ThumbprintMD5
string (read-only)

Default: ""

The MD5 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

ThumbprintSHA1
string (read-only)

Default: ""

The SHA-1 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

ThumbprintSHA256
string (read-only)

Default: ""

The SHA-256 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

Usage
string (read-only)

Default: ""

The text description of UsageFlags.

This value will be one or more of the following strings and will be separated by commas:

  • Digital Signature
  • Non-Repudiation
  • Key Encipherment
  • Data Encipherment
  • Key Agreement
  • Certificate Signing
  • CRL Signing
  • Encipher Only

If the provider is OpenSSL, the value is a comma-separated list of X.509 certificate extension names.

UsageFlags
int (read-only)

Default: 0

The flags that show intended use for the certificate. The value of UsageFlags is a combination of the following flags:

0x80Digital Signature
0x40Non-Repudiation
0x20Key Encipherment
0x10Data Encipherment
0x08Key Agreement
0x04Certificate Signing
0x02CRL Signing
0x01Encipher Only

Please see the Usage field for a text representation of UsageFlags.

This functionality currently is not available when the provider is OpenSSL.

Version
string (read-only)

Default: ""

The certificate's version number. The possible values are the strings "V1", "V2", and "V3".

Subject
string

Default: ""

The subject of the certificate used for client authentication.

This field will be populated with the full subject of the loaded certificate. When loading a certificate, the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks a random certificate in the certificate store.

The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:

FieldMeaning
CNCommon Name. This is commonly a hostname like www.server.com.
OOrganization
OUOrganizational Unit
LLocality
SState
CCountry
EEmail Address

If a field value contains a comma, it must be quoted.

Encoded
string

Default: ""

The certificate (PEM/Base64 encoded). This field is used to assign a specific certificate. The Store and Subject fields also may be used to specify a certificate.

When Encoded is set, a search is initiated in the current Store for the private key of the certificate. If the key is found, Subject is updated to reflect the full subject of the selected certificate; otherwise, Subject is set to an empty string.

EncodedB
byte []

Default: ""

The certificate (PEM/Base64 encoded). This field is used to assign a specific certificate. The Store and Subject fields also may be used to specify a certificate.

When Encoded is set, a search is initiated in the current Store for the private key of the certificate. If the key is found, Subject is updated to reflect the full subject of the selected certificate; otherwise, Subject is set to an empty string.

Constructors

public Certificate();
Public Certificate()

Creates a instance whose properties can be set. This is useful for use with when generating new certificates.

public Certificate(string certificateFile);
Public Certificate(ByVal CertificateFile As String)

Opens CertificateFile and reads out the contents as an X.509 public key.

public Certificate(byte[] encoded);
Public Certificate(ByVal Encoded As Byte())

Parses Encoded as an X.509 public key.

public Certificate(CertStoreTypes storeType, string store, string storePassword, string subject);
Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Subject As String)

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store.

After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN). The Subject parameter can also take an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load in a "Thumbprint=value" format.

public Certificate(CertStoreTypes storeType, string store, string storePassword, string subject, string configurationString);
Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Subject As String, ByVal ConfigurationString As String)

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store.

ConfigurationString is a newline-separated list of name-value pairs that may be used to modify the default behavior. Possible values include "PersistPFXKey", which shows whether or not the PFX key is persisted after performing operations with the private key. This correlates to the PKCS12_NO_PERSIST_KEY CryptoAPI option. The default value is True (the key is persisted). "Thumbprint" - an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load. When specified, this value is used to select the certificate in the store. This is applicable to the cstUser , cstMachine , cstPublicKeyFile , and cstPFXFile store types. "UseInternalSecurityAPI" shows whether the platform (default) or the internal security API is used when performing certificate-related operations.

After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN). The Subject parameter can also take an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load in a "Thumbprint=value" format.

public Certificate(CertStoreTypes storeType, string store, string storePassword, byte[] encoded);
Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Encoded As Byte())

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store.

After the store has been successfully opened, the component will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

public Certificate(CertStoreTypes storeType, byte[] store, string storePassword, string subject);
Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As Byte(), ByVal StorePassword As String, ByVal Subject As String)

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a byte array containing the certificate data. StorePassword is the password used to protect the store.

After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN). The Subject parameter can also take an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load in a "Thumbprint=value" format.

public Certificate(CertStoreTypes storeType, byte[] store, string storePassword, string subject, string configurationString);
Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As Byte(), ByVal StorePassword As String, ByVal Subject As String, ByVal ConfigurationString As String)

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a byte array containing the certificate data. StorePassword is the password used to protect the store.

After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN). The Subject parameter can also take an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load in a "Thumbprint=value" format.

public Certificate(CertStoreTypes storeType, byte[] store, string storePassword, byte[] encoded);
Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As Byte(), ByVal StorePassword As String, ByVal Encoded As Byte())

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a byte array containing the certificate data. StorePassword is the password used to protect the store.

After the store has been successfully opened, the component will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

FileAttachment Type

This describes the file being attached.

Remarks

This contains information about the location of the file that is being attached to the message.

The following fields are available:

Fields

Data
string

Default: ""

The raw data for the attachment that will be sent with your message. This field is used if InputStream and File are not set.

DataB
byte []

Default: ""

The raw data for the attachment that will be sent with your message. This field is used if InputStream and File are not set.

FileName
string

Default: ""

This field contains the path of a file on your system to be sent as an attachment with your message. Not used if InputStream is set.

InputStream
System.IO.Stream

Default: ""

When this field is set to a valid stream, the component will attach the data from the stream as the current attachment.

Name
string

Default: ""

This field contains the name of the attachment to be sent.

Constructors

public FileAttachment();
Public FileAttachment()
public FileAttachment(string fileName);
Public FileAttachment(ByVal FileName As String)
public FileAttachment(string name, string fileName);
Public FileAttachment(ByVal Name As String, ByVal FileName As String)
public FileAttachment(string name, System.IO.Stream inputStream);
Public FileAttachment(ByVal Name As String, ByVal InputStream As System.IO.Stream)
public FileAttachment(string name, System.IO.Stream inputStream, string encoding);
Public FileAttachment(ByVal Name As String, ByVal InputStream As System.IO.Stream, ByVal Encoding As String)

Firewall Type

The firewall the component will connect through.

Remarks

When connecting through a firewall, this type is used to specify different properties of the firewall, such as the firewall Host and the FirewallType.

The following fields are available:

Fields

AutoDetect
bool

Default: False

Whether to automatically detect and use firewall system settings, if available.

FirewallType
FirewallTypes

Default: 0

The type of firewall to connect through. The applicable values are as follows:

fwNone (0)No firewall (default setting).
fwTunnel (1)Connect through a tunneling proxy. Port is set to 80.
fwSOCKS4 (2)Connect through a SOCKS4 Proxy. Port is set to 1080.
fwSOCKS5 (3)Connect through a SOCKS5 Proxy. Port is set to 1080.
fwSOCKS4A (10)Connect through a SOCKS4A Proxy. Port is set to 1080.

Host
string

Default: ""

The name or IP address of the firewall (optional). If a Host is given, the requested connections will be authenticated through the specified firewall when connecting.

If this field is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, this field is set to the corresponding address. If the search is not successful, the component throws an exception.

Password
string

Default: ""

A password if authentication is to be used when connecting through the firewall. If Host is specified, the User and Password fields are used to connect and authenticate to the given firewall. If the authentication fails, the component throws an exception.

Port
int

Default: 0

The Transmission Control Protocol (TCP) port for the firewall Host. See the description of the Host field for details.

Note: This field is set automatically when FirewallType is set to a valid value. See the description of the FirewallType field for details.

User
string

Default: ""

A username if authentication is to be used when connecting through a firewall. If Host is specified, this field and the Password field are used to connect and authenticate to the given Firewall. If the authentication fails, the component throws an exception.

Constructors

public Firewall();
Public Firewall()

HTMLImage Type

This type describes an HTML-embedded image.

Remarks

Each image in the HTML message gets set when the MessageHTML property is set. You may, however, make changes to the fields for each HTMLImage before the message is sent.

The following fields are available:

Fields

Data
string

Default: ""

This field optionally specifies the image data. This may be used instead of specifying an image by file. The value specified here may be either the hex-encoded image data or the raw unencoded image data.

DataB
byte []

Default: ""

This field optionally specifies the image data. This may be used instead of specifying an image by file. The value specified here may be either the hex-encoded image data or the raw unencoded image data.

File
string

Default: ""

This field contains the name of the image files embedded into the HTML message. This value is updated every time MessageHTML is set. You may change the file names before sending (e.g., if they don't point to valid files).

Id
string

Default: ""

This field contains the content identifier for embedded images. This value is computed automatically, unless ParseHTML is False, in which case you are responsible for providing it.

ImageType
string

Default: ""

This field contains the content type for embedded images. This value is determined automatically, unless ParseHTML is False, in which case you are responsible for providing it.

Constructors

public HTMLImage();
Public HTMLImage()
public HTMLImage(string file);
Public HTMLImage(ByVal File As String)

MessageRecipient Type

This types describes the message recipient.

Remarks

This type describes who the message is sent to. It includes fields to denote the name and email address of the recipient of the message. The type of recipient must also be specified if the component is sending the message.

The following fields are available:

Fields

Address
string

Default: ""

This field contains the email address of the recipient.

Name
string

Default: ""

This field contains the name of the recipient.

Options
string

Default: ""

This field contains the recipient sending options (used only by SMTP). This must be a string of RFC-compliant recipient options (used by SMTP).

One type of option is a delivery status notification sent per recipient, which is specified by RFC 1891.

component.MessageRecipients(0).Options = "NOTIFY SUCCESS,FAILURE,DELAY";

RecipientType
EmailRecipientTypes

Default: 0

This field contains the recipient type: To, Cc, or Bcc.

Constructors

public MessageRecipient();
Public MessageRecipient()
public MessageRecipient(string address);
Public MessageRecipient(ByVal Address As String)
public MessageRecipient(string address, int recipientType);
Public MessageRecipient(ByVal Address As String, ByVal RecipientType As Integer)

Config Settings (HTMLMailer Component)

The component accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

HTMLMailer Config Settings

AttachmentEncoding[index]:   Content-Transfer-Encoding for attached file (at index).

This configuration setting allows you to set the Content-Transfer-Encoding for each attached file in the Attachments array property. Valid array indices are from 0 to AttachmentCount -1. When set to one of the following integer values, the attachment will be encoded using the specified encoding. The following encodings are supported:

07-bit
1Quoted-Printable
2Base64
38-bit
AttachmentType[index]:   Content-type for attached file (at index).

This configuration setting allows you to set the Content-Type for each attached file in the Attachments array property. Valid array indices are from 0 to AttachmentCount -1. To set the Content-Type for the attachment at index 2, you would set the string "AttachmentType[2]=application/octet-stream".

Charset:   When set, the charset Content-Type attribute will be added using the specified value.

This property is used to specify the "charset" Content-Type attribute for both the HTML (MessageHTML) and plain text (MessageText) part headers. The default value is "" (empty string) in which case the charset attribute will not be added to the Content-Type header.

ExcludeTags:   Specifies tags that will be excluded when calculating MessageText.

This property can be used to specify tags that will be excluded when the component calculates MessageText after MessageHTML has been set. Set this to a comma-separated list of tags, like "script,style". The default value is an empty string, so all tags will be included in MessageText.

MessageTextEncoding:   When set, the MessageHTML and MessageText values will be encoded using the specified encoding.

When set to one of the following integer values, both the MessageHTML and MessageText properties will be encoded using the specified encoding. The "Content-Transfer-Encoding" header will also be set for both the HTML and plain text parts. The following encodings are supported:

07-bit
1Quoted-Printable
2Base64
38-bit
OverrideFileName:   If set to true, the AttachmentName property value will be used to set the MIME part FileName attribute.

When set to True, the Name value specified will be used to set the FileName attribute of the Content-Disposition header. The default value is False, in which case, the component will use the same name as the file being added.

TempFilePath:   If set, the temporary files created during message creation will be put in the path specified.

The TempFilePath configuration sets the path at which the temporary files will be created.

UseTempFile:   Determines if temporary files are used during message creation.

When true, the component will create temporary files on disk at the path specified by TempFilePath as necessary during message creation. Set this to false, to disable the creation of temporary files. When set to false, the message will be created entirely in memory. The default value is false.

SMTP Config Settings

AllowEmptyTo:   If set to True, then the SendTo property is not required.

Normally, the SendTo property is required to send a message. If AllowEmptyTo is True, then this is not the case, and messages can be sent with just one or both of Cc and BCc set.

AuthorizationIdentity:   The value to use as the authorization identity when SASL authentication is used.

When AuthMechanism is set to amXOAUTH2, you may use this configuration setting to specify an authorization identity to be used when authenticating. In the case of amXOAUTH2, this should be your OAUTH authorization string. For instance:

Bearer ya29.AHES6ZRmS-8xPbpGetC1VbABJIBRdKm-c4X7wMVGAbgxdGt5q8Ts3Q

Note: When using amXOAUTH2, User must be specified, but Password is not required.

Charset:   When set, the message headers will be encoded using the specified Charset.

This configuration setting is used to specify the "charset" to be used to encode the message headers. For example, to use UTF-8 you can set this property to "UTF-8". The default value is "" (empty string) in which case the headers will not be encoded.

FoldHeaders:   Tells the component whether to fold the headers.

If True, the component will fold the headers if the headers are over a certain length. If False, the headers will be on one line regardless of length.

Note: This is True by default.

Hello:   The argument for HELO (herald) command to the server (defaults to local host name).

The Hello property specifies a string to send to the MailServer at connection time as an argument to the SMTP HELO command. This generally identifies the host sending mail, and that is why the Hello property defaults to the name of the local host. The property is provided in case the component does not accept the default value and a custom value (e.g., a fully qualified domain name) must be sent.

If AllowExtensions is True, the EHLO command will be sent instead of the HELO command.

KeepQueue:   If set to True, queued files are not deleted after a successful send.

Normally, ProcessQueue deletes queued files after processing them. If KeepQueue is True, then the file extension is instead changed to ".sent" and the files are not deleted.

MaxHeaderLength:   Maximum length for headers to avoid line folding (default 80).

The MaxHeaderLength specifies the maximum line length supported by the mail delivery system. Any headers longer than MaxHeaderLength are folded as specified in RFC 822.

It is generally a good idea to use a MaxHeaderLength of less than 100 bytes, although different mail relays and mail servers have different requirements for header lengths.

MessageHeadersString:   String representation of RFC822-encoded headers of the message.

This setting holds the full headers of the message in RFC 822 format. Use this along with TransferText to store the entire message in RFC 822 format.

Example: smtp1.Send(); string rawMsg = smtp1.Config("MessageHeadersString") + smtp1.Config("TransferText");

MessageIdAlgorithm:   Determines the algorithm used to hash the random MessageId.

The MessageIdAlgorithm specifies which algorithm to use in the hash for the MessageId when the property is set to "*". The default value is "SHA1".

Possible values are as follows:

  • "MD5"
  • "SHA1" (default)
  • "SHA256"

OtherHeaders:   An RFC 822 compliant string consisting of extra headers.

This is the same as the OtherHeaders property. This configuration setting is exposed for use by components that are inherited from SMTP.

ReturnPath:   Sets the Return-Path to be used for sending email.

This is the same as the ReturnPath property. This configuration setting is exposed for use by components that are inherited from SMTP.

SendRSET:   Whether to send RSET command.

By default, the component will periodically send the RSET command to the server. Changing this configuration setting to False will prevent the RSET command from being sent. This can be useful when interacting with some servers that do not respond properly to the RSET command.

StopOnBccErrors:   Instructs the component to stop sending the message if the server does not acknowledge any of the BCCs.

If this configuration setting is set to True, the component will fail the moment the server does not acknowledge a Bcc address. If it is set to False, an error will be fired for every Bcc that is not recognized by the server, but the message will be sent to the rest of the recipients. The default value is False.

StopOnCcErrors:   Instructs the component to stop sending the message if the server does not acknowledge any of the CCs.

If this configuration setting is set to True, the component will fail the moment the server does not acknowledge a Cc address. If it is set to False, an error will be fired for every Cc that is not recognized by the server, but the message will be sent to the rest of the recipients. The default value is True.

StopOnToErrors:   Instructs the component to stop sending the message if the server does not acknowledge any of the TOs.

If this configuration setting is set to True, the component will fail the moment the server does not acknowledge a To address. If it is set to False, an error will be fired for every To that is not recognized by the server, but the message will be sent to the rest of the recipients. The default value is True.

TransferText:   String representation of RFC822-encoded body of the message.

This configuration setting holds the full body of the message in RFC 822 format. Use this along with MessageHeadersString to store the entire message in RFC 822 format.

Example: smtp1.Send(); string rawMsg = smtp1.Config("MessageHeadersString") + smtp1.Config("TransferText");

TCPClient Config Settings

CloseStreamAfterTransfer:   If true, the component will close the upload or download stream after the transfer.

This configuration setting determines whether the input or output stream is closed after the transfer completes. When set to True (default), all streams will be closed after a transfer is completed. To keep streams open after the transfer of data, set this to False. The default value is True.

ConnectionTimeout:   Sets a separate timeout value for establishing a connection.

When set, this configuration setting allows you to specify a different timeout value for establishing a connection. Otherwise, the component will use Timeout for establishing a connection and transmitting/receiving data.

FirewallAutoDetect:   Tells the component whether or not to automatically detect and use firewall system settings, if available.

This configuration setting is provided for use by components that do not directly expose Firewall properties.

FirewallHost:   Name or IP address of firewall (optional).

If a FirewallHost is given, requested connections will be authenticated through the specified firewall when connecting.

If the FirewallHost setting is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, the FirewallHost setting is set to the corresponding address. If the search is not successful, an error is returned.

Note: This setting is provided for use by components that do not directly expose Firewall properties.

FirewallListener:   If true, the component binds to a SOCKS firewall as a server (TCPClient only).

This entry is for TCPClient only and does not work for other components that descend from TCPClient.

If this entry is set, the component acts as a server. RemoteHost and RemotePort are used to tell the SOCKS firewall in which address and port to listen to. The firewall rules may ignore RemoteHost, and it is recommended that RemoteHost be set to empty string in this case.

RemotePort is the port in which the firewall will listen to. If set to 0, the firewall will select a random port. The binding (address and port) is provided through the ConnectionStatus event.

The connection to the firewall is made by calling the Connect method.

FirewallPassword:   Password to be used if authentication is to be used when connecting through the firewall.

If FirewallHost is specified, the FirewallUser and FirewallPassword settings are used to connect and authenticate to the given firewall. If the authentication fails, the component throws an exception.

Note: This setting is provided for use by components that do not directly expose Firewall properties.

FirewallPort:   The TCP port for the FirewallHost;.

The FirewallPort is set automatically when FirewallType is set to a valid value.

Note: This configuration setting is provided for use by components that do not directly expose Firewall properties.

FirewallType:   Determines the type of firewall to connect through.

Possible values are as follows:

0No firewall (default setting).
1Connect through a tunneling proxy. FirewallPort is set to 80.
2Connect through a SOCKS4 Proxy. FirewallPort is set to 1080.
3Connect through a SOCKS5 Proxy. FirewallPort is set to 1080.
10Connect through a SOCKS4A Proxy. FirewallPort is set to 1080.

Note: This setting is provided for use by components that do not directly expose Firewall properties.

FirewallUser:   A user name if authentication is to be used connecting through a firewall.

If the FirewallHost is specified, the FirewallUser and FirewallPassword settings are used to connect and authenticate to the Firewall. If the authentication fails, the component throws an exception.

Note: This setting is provided for use by components that do not directly expose Firewall properties.

KeepAliveInterval:   The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.

When set, TCPKeepAlive will automatically be set to True. A TCP keep-alive packet will be sent after a period of inactivity as defined by KeepAliveTime. If no acknowledgment is received from the remote host, the keep-alive packet will be sent again. This configuration setting specifies the interval at which the successive keep-alive packets are sent in milliseconds. This system default if this value is not specified here is 1 second.

Note: This value is not applicable in macOS.

KeepAliveTime:   The inactivity time in milliseconds before a TCP keep-alive packet is sent.

When set, TCPKeepAlive will automatically be set to True. By default, the operating system will determine the time a connection is idle before a Transmission Control Protocol (TCP) keep-alive packet is sent. This system default if this value is not specified here is 2 hours. In many cases, a shorter interval is more useful. Set this value to the desired interval in milliseconds.

Linger:   When set to True, connections are terminated gracefully.

This property controls how a connection is closed. The default is True.

In the case that Linger is True (default), two scenarios determine how long the connection will linger. In the first, if LingerTime is 0 (default), the system will attempt to send pending data for a connection until the default IP timeout expires.

In the second scenario, if LingerTime is a positive value, the system will attempt to send pending data until the specified LingerTime is reached. If this attempt fails, then the system will reset the connection.

The default behavior (which is also the default mode for stream sockets) might result in a long delay in closing the connection. Although the component returns control immediately, the system could hold system resources until all pending data are sent (even after your application closes).

Setting this property to False forces an immediate disconnection. If you know that the other side has received all the data you sent (e.g., by a client acknowledgment), setting this property to False might be the appropriate course of action.

LingerTime:   Time in seconds to have the connection linger.

LingerTime is the time, in seconds, the socket connection will linger. This value is 0 by default, which means it will use the default IP timeout.

LocalHost:   The name of the local host through which connections are initiated or accepted.

The LocalHost setting contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multihomed hosts (machines with more than one IP interface), setting LocalHost to the value of an interface will make the component initiate connections (or accept in the case of server components) only through that interface.

If the component is connected, the LocalHost setting shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multihomed hosts (machines with more than one IP interface).

LocalPort:   The port in the local host where the component binds.

This configuration setting must be set before a connection is attempted. It instructs the component to bind to a specific port (or communication endpoint) in the local machine.

Setting this to 0 (default) enables the system to choose a port at random. The chosen port will be shown by LocalPort after the connection is established.

LocalPort cannot be changed once a connection is made. Any attempt to set this when a connection is active will generate an error.

This configuration setting is useful when trying to connect to services that require a trusted port on the client side. An example is the remote shell (rsh) service in UNIX systems.

MaxLineLength:   The maximum amount of data to accumulate when no EOL is found.

MaxLineLength is the size of an internal buffer, which holds received data while waiting for an EOL string.

If an EOL string is found in the input stream before MaxLineLength bytes are received, the DataIn event is fired with the EOL parameter set to True, and the buffer is reset.

If no EOL is found, and MaxLineLength bytes are accumulated in the buffer, the DataIn event is fired with the EOL parameter set to False, and the buffer is reset.

The minimum value for MaxLineLength is 256 bytes. The default value is 2048 bytes.

MaxTransferRate:   The transfer rate limit in bytes per second.

This configuration setting can be used to throttle outbound TCP traffic. Set this to the number of bytes to be sent per second. By default, this is not set and there is no limit.

ProxyExceptionsList:   A semicolon separated list of hosts and IPs to bypass when using a proxy.

This configuration setting optionally specifies a semicolon-separated list of hostnames or IP addresses to bypass when a proxy is in use. When requests are made to hosts specified in this property, the proxy will not be used. For instance:

www.google.com;www.nsoftware.com

TCPKeepAlive:   Determines whether or not the keep alive socket option is enabled.

If set to True, the socket's keep-alive option is enabled and keep-alive packets will be sent periodically to maintain the connection. Set KeepAliveTime and KeepAliveInterval to configure the timing of the keep-alive packets.

Note: This value is not applicable in Java.

TcpNoDelay:   Whether or not to delay when sending packets.

When set to True, the socket will send all data that are ready to send at once. When set to False, the socket will send smaller buffered packets of data at small intervals. This is known as the Nagle algorithm.

By default, this configuration setting is set to False.

UseIPv6:   Whether to use IPv6.

When set to 0 (default), the component will use IPv4 exclusively. When set to 1, the component will use IPv6 exclusively. To instruct the component to prefer IPv6 addresses, but use IPv4 if IPv6 is not supported on the system, this setting should be set to 2. The default value is 0. Possible values are as follows:

0 IPv4 only
1 IPv6 only
2 IPv6 with IPv4 fallback
UseNTLMv2:   Whether to use NTLM V2.

When authenticating with NTLM, this setting specifies whether NTLM V2 is used. By default this value is False and NTLM V1 will be used. Set this to True to use NTLM V2.

SSL Config Settings

CACertFilePaths:   The paths to CA certificate files when using Mono on Unix/Linux.

This configuration setting specifies the paths on disk to certificate authority (CA) certificate files when using Mono on Unix/Linux. It is not applicable in any other circumstances.

The value is formatted as a list of paths separated by semicolons. The component will check for the existence of each file in the order specified. When a file is found, the CA certificates within the file will be loaded and used to determine the validity of server or client certificates.

The default value is as follows:

/etc/ssl/ca-bundle.pem;/etc/pki/tls/certs/ca-bundle.crt;/etc/ssl/certs/ca-certificates.crt;/etc/pki/tls/cacert.pem

LogSSLPackets:   Controls whether SSL packets are logged when using the internal security API.

When SSLProvider is set to Internal, this configuration setting controls whether Secure Sockets Layer (SSL) packets should be logged. By default, this configuration setting is False, as it is useful only for debugging purposes.

When enabled, SSL packet logs are output using the SSLStatus event, which will fire each time an SSL packet is sent or received.

Enabling this configuration setting has no effect if SSLProvider is set to Platform.

ReuseSSLSession:   Determines if the SSL session is reused.

If set to True, the component will reuse the context if and only if the following criteria are met:

  • The target host name is the same.
  • The system cache entry has not expired (default timeout is 10 hours).
  • The application process that calls the function is the same.
  • The logon session is the same.
  • The instance of the component is the same.

SSLCACerts:   A newline separated list of CA certificates to be included when performing an SSL handshake.

When SSLProvider is set to Internal, this configuration setting specifies one or more CA certificates to be included with the SSLCert property. Some servers or clients require the entire chain, including CA certificates, to be presented when performing SSL authentication. The value of this configuration setting is a newline-separated (CR/LF) list of certificates. For instance:

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert ...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert ...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

SSLCheckCRL:   Whether to check the Certificate Revocation List for the server certificate.

This configuration setting specifies whether the component will check the Certificate Revocation List (CRL) specified by the server certificate. If set to 1 or 2, the component will first obtain the list of CRL URLs from the server certificate's CRL distribution points extension. The component will then make HTTP requests to each CRL endpoint to check the validity of the server's certificate. If the certificate has been revoked or any other issues are found during validation the component throws an exception.

When set to 0 (default), the CRL check will not be performed by the component. When set to 1, it will attempt to perform the CRL check, but it will continue without an error if the server's certificate does not support CRL. When set to 2, it will perform the CRL check and will throw an error if CRL is not supported.

This configuration setting is supported only in the Java, C#, and C++ editions. In the C++ edition, it is supported only on Windows operating systems.

SSLCheckOCSP:   Whether to use OCSP to check the status of the server certificate.

This configuration setting specifies whether the component will use OCSP to check the validity of the server certificate. If set to 1 or 2, the component will first obtain the Online Certificate Status Protocol (OCSP) URL from the server certificate's OCSP extension. The component will then locate the issuing certificate and make an HTTP request to the OCSP endpoint to check the validity of the server's certificate. If the certificate has been revoked or any other issues are found during validation, the component throws an exception.

When set to 0 (default), the component will not perform an OCSP check. When set to 1, it will attempt to perform the OCSP check, but it will continue without an error if the server's certificate does not support OCSP. When set to 2, it will perform the OCSP check and will throw an error if OCSP is not supported.

This configuration setting is supported only in the Java, C#, and C++ editions. In the C++ edition, it is supported only on Windows operating systems.

SSLCipherStrength:   The minimum cipher strength used for bulk encryption.

This minimum cipher strength is largely dependent on the security modules installed on the system. If the cipher strength specified is not supported, an error will be returned when connections are initiated.

Note: This configuration setting contains the minimum cipher strength requested from the security library. The actual cipher strength used for the connection is shown by the SSLStatus event.

Use this configuration setting with caution. Requesting a lower cipher strength than necessary could potentially cause serious security vulnerabilities in your application.

When the provider is OpenSSL, SSLCipherStrength is currently not supported. This functionality is instead made available through the OpenSSLCipherList configuration setting.

SSLClientCACerts:   A newline separated list of CA certificates to use during SSL client certificate validation.

This configuration setting is only applicable to server components (e.g., TCPServer) see SSLServerCACerts for client components (e.g., TCPClient). This setting can be used to optionally specify one or more CA certificates to be used when verifying the client certificate that is presented by the client during the SSL handshake when SSLAuthenticateClients is enabled. When verifying the client's certificate, the certificates trusted by the system will be used as part of the verification process. If the client's CA certificates are not installed to the trusted system store, they may be specified here so they are included when performing the verification process. This configuration setting should be set only if the client's CA certificates are not already trusted on the system and cannot be installed to the trusted system store.

The value of this configuration setting is a newline-separated (CR/LF) list of certificates. For instance:

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert ...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert ...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

SSLEnabledCipherSuites:   The cipher suite to be used in an SSL negotiation.

This configuration setting enables the cipher suites to be used in SSL negotiation.

By default, the enabled cipher suites will include all available ciphers ("*").

The special value "*" means that the component will pick all of the supported cipher suites. If SSLEnabledCipherSuites is set to any other value, only the specified cipher suites will be considered.

Multiple cipher suites are separated by semicolons.

Example values when SSLProvider is set to Platform include the following: obj.config("SSLEnabledCipherSuites=*"); obj.config("SSLEnabledCipherSuites=CALG_AES_256"); obj.config("SSLEnabledCipherSuites=CALG_AES_256;CALG_3DES"); Possible values when SSLProvider is set to Platform include the following:

  • CALG_3DES
  • CALG_3DES_112
  • CALG_AES
  • CALG_AES_128
  • CALG_AES_192
  • CALG_AES_256
  • CALG_AGREEDKEY_ANY
  • CALG_CYLINK_MEK
  • CALG_DES
  • CALG_DESX
  • CALG_DH_EPHEM
  • CALG_DH_SF
  • CALG_DSS_SIGN
  • CALG_ECDH
  • CALG_ECDH_EPHEM
  • CALG_ECDSA
  • CALG_ECMQV
  • CALG_HASH_REPLACE_OWF
  • CALG_HUGHES_MD5
  • CALG_HMAC
  • CALG_KEA_KEYX
  • CALG_MAC
  • CALG_MD2
  • CALG_MD4
  • CALG_MD5
  • CALG_NO_SIGN
  • CALG_OID_INFO_CNG_ONLY
  • CALG_OID_INFO_PARAMETERS
  • CALG_PCT1_MASTER
  • CALG_RC2
  • CALG_RC4
  • CALG_RC5
  • CALG_RSA_KEYX
  • CALG_RSA_SIGN
  • CALG_SCHANNEL_ENC_KEY
  • CALG_SCHANNEL_MAC_KEY
  • CALG_SCHANNEL_MASTER_HASH
  • CALG_SEAL
  • CALG_SHA
  • CALG_SHA1
  • CALG_SHA_256
  • CALG_SHA_384
  • CALG_SHA_512
  • CALG_SKIPJACK
  • CALG_SSL2_MASTER
  • CALG_SSL3_MASTER
  • CALG_SSL3_SHAMD5
  • CALG_TEK
  • CALG_TLS1_MASTER
  • CALG_TLS1PRF
Example values when SSLProvider is set to Internalinclude the following: obj.config("SSLEnabledCipherSuites=*"); obj.config("SSLEnabledCipherSuites=TLS_DHE_DSS_WITH_AES_128_CBC_SHA"); obj.config("SSLEnabledCipherSuites=TLS_DHE_DSS_WITH_AES_128_CBC_SHA;TLS_ECDH_RSA_WITH_AES_128_CBC_SHA"); Possible values when SSLProvider is set to Internal include the following:
  • TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
  • TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
  • TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
  • TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
  • TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384
  • TLS_RSA_WITH_AES_256_GCM_SHA384
  • TLS_RSA_WITH_AES_128_GCM_SHA256
  • TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256
  • TLS_DHE_DSS_WITH_AES_256_GCM_SHA384
  • TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
  • TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384
  • TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256
  • TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
  • TLS_DHE_DSS_WITH_AES_128_GCM_SHA256
  • TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
  • TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384
  • TLS_DHE_DSS_WITH_AES_256_CBC_SHA256
  • TLS_RSA_WITH_AES_256_CBC_SHA256
  • TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
  • TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384
  • TLS_DHE_RSA_WITH_AES_256_CBC_SHA256
  • TLS_DHE_RSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
  • TLS_RSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256
  • TLS_DHE_DSS_WITH_AES_128_CBC_SHA256
  • TLS_RSA_WITH_AES_256_CBC_SHA
  • TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
  • TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
  • TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA
  • TLS_DHE_RSA_WITH_AES_256_CBC_SHA
  • TLS_ECDH_RSA_WITH_AES_256_CBC_SHA
  • TLS_DHE_DSS_WITH_AES_256_CBC_SHA
  • TLS_RSA_WITH_AES_128_CBC_SHA
  • TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
  • TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
  • TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA
  • TLS_ECDH_RSA_WITH_AES_128_CBC_SHA
  • TLS_DHE_RSA_WITH_AES_128_CBC_SHA
  • TLS_DHE_DSS_WITH_AES_128_CBC_SHA
  • TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA
  • TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA
  • TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA
  • TLS_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_RSA_WITH_DES_CBC_SHA
  • TLS_DHE_RSA_WITH_DES_CBC_SHA
  • TLS_DHE_DSS_WITH_DES_CBC_SHA
  • TLS_RSA_WITH_RC4_128_MD5
  • TLS_RSA_WITH_RC4_128_SHA

When TLS 1.3 is negotiated (see SSLEnabledProtocols), only the following cipher suites are supported:

  • TLS_AES_256_GCM_SHA384
  • TLS_CHACHA20_POLY1305_SHA256
  • TLS_AES_128_GCM_SHA256

SSLEnabledCipherSuites is used together with SSLCipherStrength.

SSLEnabledProtocols:   Used to enable/disable the supported security protocols.

This configuration setting is used to enable or disable the supported security protocols.

Not all supported protocols are enabled by default. The default value is 4032 for client components, and 3072 for server components. To specify a combination of enabled protocol versions set this config to the binary OR of one or more of the following values:

TLS1.312288 (Hex 3000)
TLS1.23072 (Hex C00) (Default - Client and Server)
TLS1.1768 (Hex 300) (Default - Client)
TLS1 192 (Hex C0) (Default - Client)
SSL3 48 (Hex 30)
SSL2 12 (Hex 0C)

Note that only TLS 1.2 is enabled for server components that accept incoming connections. This adheres to industry standards to ensure a secure connection. Client components enable TLS 1.0, TLS 1.1, and TLS 1.2 by default and will negotiate the highest mutually supported version when connecting to a server, which should be TLS 1.2 in most cases.

SSLEnabledProtocols: Transport Layer Security (TLS) 1.3 Notes:

By default when TLS 1.3 is enabled, the component will use the internal TLS implementation when the SSLProvider is set to Automatic for all editions.

In editions that are designed to run on Windows, SSLProvider can be set to Platform to use the platform implementation instead of the internal implementation. When configured in this manner, please note that the platform provider is supported only on Windows 11/Windows Server 2022 and up. The default internal provider is available on all platforms and is not restricted to any specific OS version.

If set to 1 (Platform provider), please be aware of the following notes:

  • The platform provider is available only on Windows 11/Windows Server 2022 and up.
  • SSLEnabledCipherSuites and other similar SSL configuration settings are not supported.
  • If SSLEnabledProtocols includes both TLS 1.3 and TLS 1.2, these restrictions are still applicable even if TLS 1.2 is negotiated. Enabling TLS 1.3 with the platform provider changes the implementation used for all TLS versions.

SSLEnabledProtocols: SSL2 and SSL3 Notes:

SSL 2.0 and 3.0 are not supported by the component when the SSLProvider is set to internal. To use SSL 2.0 or SSL 3.0, the platform security API must have the protocols enabled and SSLProvider needs to be set to platform.

SSLEnableRenegotiation:   Whether the renegotiation_info SSL extension is supported.

This configuration setting specifies whether the renegotiation_info SSL extension will be used in the request when using the internal security API. This configuration setting is false by default, but it can be set to true to enable the extension.

This configuration setting is applicable only when SSLProvider is set to Internal.

SSLIncludeCertChain:   Whether the entire certificate chain is included in the SSLServerAuthentication event.

This configuration setting specifies whether the Encoded parameter of the SSLServerAuthentication event contains the full certificate chain. By default this value is False and only the leaf certificate will be present in the Encoded parameter of the SSLServerAuthentication event.

If set to True, all certificates returned by the server will be present in the Encoded parameter of the SSLServerAuthentication event. This includes the leaf certificate, any intermediate certificate, and the root certificate.

Note: When SSLProvider is set to Internal this value is automatically set to true. This is needed for proper validation when using the internal provider.

SSLKeyLogFile:   The location of a file where per-session secrets are written for debugging purposes.

This configuration setting optionally specifies the full path to a file on disk where per-session secrets are stored for debugging purposes.

When set, the component will save the session secrets in the same format as the SSLKEYLOGFILE environment variable functionality used by most major browsers and tools, such as Chrome, Firefox, and cURL. This file can then be used in tools such as Wireshark to decrypt TLS traffic for debugging purposes. When writing to this file, the component will only append, it will not overwrite previous values.

Note: This configuration setting is applicable only when SSLProvider is set to Internal.

SSLNegotiatedCipher:   Returns the negotiated cipher suite.

This configuration setting returns the cipher suite negotiated during the SSL handshake.

Note: For server components (e.g., TCPServer), this is a per-connection configuration setting accessed by passing the ConnectionId. For example: server.Config("SSLNegotiatedCipher[connId]");

SSLNegotiatedCipherStrength:   Returns the negotiated cipher suite strength.

This configuration setting returns the strength of the cipher suite negotiated during the SSL handshake.

Note: For server components (e.g., TCPServer), this is a per-connection configuration setting accessed by passing the ConnectionId. For example: server.Config("SSLNegotiatedCipherStrength[connId]");

SSLNegotiatedCipherSuite:   Returns the negotiated cipher suite.

This configuration setting returns the cipher suite negotiated during the SSL handshake represented as a single string.

Note: For server components (e.g., TCPServer), this is a per-connection configuration setting accessed by passing the ConnectionId. For example: server.Config("SSLNegotiatedCipherSuite[connId]");

SSLNegotiatedKeyExchange:   Returns the negotiated key exchange algorithm.

This configuration setting returns the key exchange algorithm negotiated during the SSL handshake.

Note: For server components (e.g., TCPServer), this is a per-connection configuration setting accessed by passing the ConnectionId. For example: server.Config("SSLNegotiatedKeyExchange[connId]");

SSLNegotiatedKeyExchangeStrength:   Returns the negotiated key exchange algorithm strength.

This configuration setting returns the strength of the key exchange algorithm negotiated during the SSL handshake.

Note: For server components (e.g., TCPServer), this is a per-connection configuration setting accessed by passing the ConnectionId. For example: server.Config("SSLNegotiatedKeyExchangeStrength[connId]");

SSLNegotiatedVersion:   Returns the negotiated protocol version.

This configuration setting returns the protocol version negotiated during the SSL handshake.

Note: For server components (e.g., TCPServer), this is a per-connection configuration setting accessed by passing the ConnectionId. For example: server.Config("SSLNegotiatedVersion[connId]");

SSLSecurityFlags:   Flags that control certificate verification.

The following flags are defined (specified in hexadecimal notation). They can be ORed together to exclude multiple conditions:

0x00000001Ignore time validity status of certificate.
0x00000002Ignore time validity status of CTL.
0x00000004Ignore non-nested certificate times.
0x00000010Allow unknown certificate authority.
0x00000020Ignore wrong certificate usage.
0x00000100Ignore unknown certificate revocation status.
0x00000200Ignore unknown CTL signer revocation status.
0x00000400Ignore unknown certificate authority revocation status.
0x00000800Ignore unknown root revocation status.
0x00008000Allow test root certificate.
0x00004000Trust test root certificate.
0x80000000Ignore non-matching CN (certificate CN non-matching server name).

This functionality is currently not available in Java or when the provider is OpenSSL.

SSLServerCACerts:   A newline separated list of CA certificates to use during SSL server certificate validation.

This configuration setting is only used by client components (e.g., TCPClient) see SSLClientCACerts for server components (e.g., TCPServer). This configuration setting can be used to optionally specify one or more CA certificates to be used when connecting to the server and verifying the server certificate. When verifying the server's certificate, the certificates trusted by the system will be used as part of the verification process. If the server's CA certificates are not installed to the trusted system store, they may be specified here so they are included when performing the verification process. This configuration setting should be set only if the server's CA certificates are not already trusted on the system and cannot be installed to the trusted system store.

The value of this configuration setting is a newline-separated (CR/LF) list of certificates. For instance:

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

TLS12SignatureAlgorithms:   Defines the allowed TLS 1.2 signature algorithms when SSLProvider is set to Internal.

This configuration setting specifies the allowed server certificate signature algorithms when SSLProvider is set to Internal and SSLEnabledProtocols is set to allow TLS 1.2.

When specified the component will verify that the server certificate signature algorithm is among the values specified in this configuration setting. If the server certificate signature algorithm is unsupported, the component throws an exception.

The format of this value is a comma-separated list of hash-signature combinations. For instance: component.SSLProvider = TCPClientSSLProviders.sslpInternal; component.Config("SSLEnabledProtocols=3072"); //TLS 1.2 component.Config("TLS12SignatureAlgorithms=sha256-rsa,sha256-dsa,sha1-rsa,sha1-dsa"); The default value for this configuration setting is sha512-ecdsa,sha512-rsa,sha512-dsa,sha384-ecdsa,sha384-rsa,sha384-dsa,sha256-ecdsa,sha256-rsa,sha256-dsa,sha224-ecdsa,sha224-rsa,sha224-dsa,sha1-ecdsa,sha1-rsa,sha1-dsa.

To not restrict the server's certificate signature algorithm, specify an empty string as the value for this configuration setting, which will cause the signature_algorithms TLS 1.2 extension to not be sent.

TLS12SupportedGroups:   The supported groups for ECC.

This configuration setting specifies a comma-separated list of named groups used in TLS 1.2 for ECC.

The default value is ecdhe_secp256r1,ecdhe_secp384r1,ecdhe_secp521r1.

When using TLS 1.2 and SSLProvider is set to Internal, the values refer to the supported groups for ECC. The following values are supported:

  • "ecdhe_secp256r1" (default)
  • "ecdhe_secp384r1" (default)
  • "ecdhe_secp521r1" (default)

TLS13KeyShareGroups:   The groups for which to pregenerate key shares.

This configuration setting specifies a comma-separated list of named groups used in TLS 1.3 for key exchange. The groups specified here will have key share data pregenerated locally before establishing a connection. This can prevent an additional roundtrip during the handshake if the group is supported by the server.

The default value is set to balance common supported groups and the computational resources required to generate key shares. As a result, only some groups are included by default in this configuration setting.

Note: All supported groups can always be used during the handshake even if not listed here, but if a group is used that is not present in this list, it will incur an additional roundtrip and time to generate the key share for that group.

In most cases, this configuration setting does not need to be modified. This should be modified only if there is a specific reason to do so.

The default value is ecdhe_x25519,ecdhe_secp256r1,ecdhe_secp384r1,ffdhe_2048,ffdhe_3072

The values are ordered from most preferred to least preferred. The following values are supported:

  • "ecdhe_x25519" (default)
  • "ecdhe_x448"
  • "ecdhe_secp256r1" (default)
  • "ecdhe_secp384r1" (default)
  • "ecdhe_secp521r1"
  • "ffdhe_2048" (default)
  • "ffdhe_3072" (default)
  • "ffdhe_4096"
  • "ffdhe_6144"
  • "ffdhe_8192"

TLS13SignatureAlgorithms:   The allowed certificate signature algorithms.

This configuration setting holds a comma-separated list of allowed signature algorithms. Possible values include the following:

  • "ed25519" (default)
  • "ed448" (default)
  • "ecdsa_secp256r1_sha256" (default)
  • "ecdsa_secp384r1_sha384" (default)
  • "ecdsa_secp521r1_sha512" (default)
  • "rsa_pkcs1_sha256" (default)
  • "rsa_pkcs1_sha384" (default)
  • "rsa_pkcs1_sha512" (default)
  • "rsa_pss_sha256" (default)
  • "rsa_pss_sha384" (default)
  • "rsa_pss_sha512" (default)
The default value is rsa_pss_sha256,rsa_pss_sha384,rsa_pss_sha512,rsa_pkcs1_sha256,rsa_pkcs1_sha384,rsa_pkcs1_sha512,ecdsa_secp256r1_sha256,ecdsa_secp384r1_sha384,ecdsa_secp521r1_sha512,ed25519,ed448. This configuration setting is applicable only when SSLEnabledProtocols includes TLS 1.3.
TLS13SupportedGroups:   The supported groups for (EC)DHE key exchange.

This configuration setting specifies a comma-separated list of named groups used in TLS 1.3 for key exchange. This configuration setting should be modified only if there is a specific reason to do so.

The default value is ecdhe_x25519,ecdhe_x448,ecdhe_secp256r1,ecdhe_secp384r1,ecdhe_secp521r1,ffdhe_2048,ffdhe_3072,ffdhe_4096,ffdhe_6144,ffdhe_8192

The values are ordered from most preferred to least preferred. The following values are supported:

  • "ecdhe_x25519" (default)
  • "ecdhe_x448" (default)
  • "ecdhe_secp256r1" (default)
  • "ecdhe_secp384r1" (default)
  • "ecdhe_secp521r1" (default)
  • "ffdhe_2048" (default)
  • "ffdhe_3072" (default)
  • "ffdhe_4096" (default)
  • "ffdhe_6144" (default)
  • "ffdhe_8192" (default)

Socket Config Settings

AbsoluteTimeout:   Determines whether timeouts are inactivity timeouts or absolute timeouts.

If AbsoluteTimeout is set to True, any method that does not complete within Timeout seconds will be aborted. By default, AbsoluteTimeout is False, and the timeout is an inactivity timeout.

Note: This option is not valid for User Datagram Protocol (UDP) ports.

FirewallData:   Used to send extra data to the firewall.

When the firewall is a tunneling proxy, use this property to send custom (additional) headers to the firewall (e.g., headers for custom authentication schemes).

InBufferSize:   The size in bytes of the incoming queue of the socket.

This is the size of an internal queue in the Transmission Control Protocol (TCP)/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. In some cases, increasing the value of the InBufferSize setting can provide significant improvements in performance.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the component is activated the InBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

OutBufferSize:   The size in bytes of the outgoing queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. In some cases, increasing the value of the OutBufferSize setting can provide significant improvements in performance.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the component is activated the OutBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

Base Config Settings

BuildInfo:   Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

GUIAvailable:   Whether or not a message loop is available for processing events.

In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The component will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the component does not attempt to process external events.

LicenseInfo:   Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a component is using. It will return the following information:

  • Product: The product the license is for.
  • Product Key: The key the license was generated from.
  • License Source: Where the license was found (e.g., RuntimeLicense, License File).
  • License Type: The type of license installed (e.g., Royalty Free, Single Server).
  • Last Valid Build: The last valid build number for which the license will work.
MaskSensitiveData:   Whether sensitive data is masked in log messages.

In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to true to mask sensitive data. The default is true.

This setting only works on these components: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

UseFIPSCompliantAPI:   Tells the component whether or not to use FIPS certified APIs.

When set to true, the component will utilize the underlying operating system's certified APIs. Java editions, regardless of OS, utilize Bouncy Castle Federal Information Processing Standards (FIPS), while all other Windows editions make use of Microsoft security libraries.

FIPS mode can be enabled by setting the UseFIPSCompliantAPI configuration setting to true. This is a static setting that applies to all instances of all components of the toolkit within the process. It is recommended to enable or disable this setting once before the component has been used to establish a connection. Enabling FIPS while an instance of the component is active and connected may result in unexpected behavior.

For more details, please see the FIPS 140-2 Compliance article.

Note: This setting is applicable only on Windows.

Note: Enabling FIPS compliance requires a special license; please contact sales@nsoftware.com for details.

UseInternalSecurityAPI:   Whether or not to use the system security libraries or an internal implementation.

When set to false, the component will use the system security libraries by default to perform cryptographic functions where applicable. In this case, calls to unmanaged code will be made. In certain environments, this is not desirable. To use a completely managed security implementation, set this setting to true.

Setting this configuration setting to true tells the component to use the internal implementation instead of using the system security libraries.

On Windows, this setting is set to false by default. On Linux/macOS, this setting is set to true by default.

If using the .NET Standard Library, this setting will be true on all platforms. The .NET Standard library does not support using the system security libraries.

Note: This setting is static. The value set is applicable to all components used in the application.

When this value is set, the product's system dynamic link library (DLL) is no longer required as a reference, as all unmanaged code is stored in that file.

Trappable Errors (HTMLMailer Component)

HTMLMailer Errors

169   Invalid image index (out of range).
170   Invalid attachment index (out of range).

The component may also return one of the following error codes, which are inherited from other components.

MIME Errors

3   Can't create the file for write (illegal name or disk is write-protected).
4   Can't open the file for read (doesn't exist?).
5   Can't read from file.
6   Can't write to file (disk full?).
280   Invalid Part Index.
281   Unknown MIME type.
282   No MIME-boundary found.
283   No file given.
284   The component is busy.
285   Can't create a temporary file to decode the data.
286   Can't read Message file.
287   No header separator found.
289   No separator found.
290   Input stream must have seeking enabled.

SMTP Errors

118   Firewall Error. Error message contains detailed description.
161   SMTP protocol error. Description contains the server reply.
162   Error communicating with server. Error text is attached.
163   Please specify a MailServer.
164   Please specify a sender (From).
165   Please specify a recipient.
166   Busy executing current method.
301   Operation interrupted.
302   Cannot open AttachedFile.

The component may also return one of the following error codes, which are inherited from other components.

SSLClient Errors

100   You cannot change the RemotePort at this time. A connection is in progress.
101   You cannot change the RemoteHost (Server) at this time. A connection is in progress.
102   The RemoteHost address is invalid (0.0.0.0).
104   Already connected. If you want to reconnect, close the current connection first.
106   You cannot change the LocalPort at this time. A connection is in progress.
107   You cannot change the LocalHost at this time. A connection is in progress.
112   You cannot change MaxLineLength at this time. A connection is in progress.
116   RemotePort cannot be zero. Please specify a valid service port number.
117   You cannot change the UseConnection option while the component is active.
135   Operation would block.
201   Timeout.
211   Action impossible in control's present state.
212   Action impossible while not connected.
213   Action impossible while listening.
301   Timeout.
303   Could not open file.
434   Unable to convert string to selected CodePage.
1105   Already connecting. If you want to reconnect, close the current connection first.
1117   You need to connect first.
1119   You cannot change the LocalHost at this time. A connection is in progress.
1120   Connection dropped by remote host.

SSL Errors

270   Cannot load specified security library.
271   Cannot open certificate store.
272   Cannot find specified certificate.
273   Cannot acquire security credentials.
274   Cannot find certificate chain.
275   Cannot verify certificate chain.
276   Error during handshake.
280   Error verifying certificate.
281   Could not find client certificate.
282   Could not find server certificate.
283   Error encrypting data.
284   Error decrypting data.

TCP/IP Errors

10004   [10004] Interrupted system call.
10009   [10009] Bad file number.
10013   [10013] Access denied.
10014   [10014] Bad address.
10022   [10022] Invalid argument.
10024   [10024] Too many open files.
10035   [10035] Operation would block.
10036   [10036] Operation now in progress.
10037   [10037] Operation already in progress.
10038   [10038] Socket operation on nonsocket.
10039   [10039] Destination address required.
10040   [10040] Message is too long.
10041   [10041] Protocol wrong type for socket.
10042   [10042] Bad protocol option.
10043   [10043] Protocol is not supported.
10044   [10044] Socket type is not supported.
10045   [10045] Operation is not supported on socket.
10046   [10046] Protocol family is not supported.
10047   [10047] Address family is not supported by protocol family.
10048   [10048] Address already in use.
10049   [10049] Cannot assign requested address.
10050   [10050] Network is down.
10051   [10051] Network is unreachable.
10052   [10052] Net dropped connection or reset.
10053   [10053] Software caused connection abort.
10054   [10054] Connection reset by peer.
10055   [10055] No buffer space available.
10056   [10056] Socket is already connected.
10057   [10057] Socket is not connected.
10058   [10058] Cannot send after socket shutdown.
10059   [10059] Too many references, cannot splice.
10060   [10060] Connection timed out.
10061   [10061] Connection refused.
10062   [10062] Too many levels of symbolic links.
10063   [10063] File name is too long.
10064   [10064] Host is down.
10065   [10065] No route to host.
10066   [10066] Directory is not empty
10067   [10067] Too many processes.
10068   [10068] Too many users.
10069   [10069] Disc Quota Exceeded.
10070   [10070] Stale NFS file handle.
10071   [10071] Too many levels of remote in path.
10091   [10091] Network subsystem is unavailable.
10092   [10092] WINSOCK DLL Version out of range.
10093   [10093] Winsock is not loaded yet.
11001   [11001] Host not found.
11002   [11002] Nonauthoritative 'Host not found' (try again or check DNS setup).
11003   [11003] Nonrecoverable errors: FORMERR, REFUSED, NOTIMP.
11004   [11004] Valid name, no data record (check DNS setup).