This property contains the recipient sending options (used only by SMTP).
def get_message_recipient_options(recipient_index: int) -> str: ... def set_message_recipient_options(recipient_index: int, value: str) -> None: ...
This property 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.
control.MessageRecipientOptions(0) = "NOTIFY SUCCESS,FAILURE,DELAY"
The size of the array is controlled by the message_recipient_count property.