The Etag of the file being sent.
property Etag: String read get_Etag write set_Etag;
This specifies the Etag for the file. This value should be set to an empty string the first time a file is sent using the Restart command. The component will generate a unique Etag based on the processed contents of the file and set this property when sending begins.
If a file is interrupted, this value must be set when Restart is called to resume transfer of the already processed file.