Bounce address

As envelope sender (English for, envelope - sender ') or "Sender" is the e-mail address that denotes that during a SMTP handshake according to RFC 5321 as a parameter of MAIL FROM: is passed.

The designation Envelope (English for, envelope ',' shell ' ) is selected based on the envelope. As in the letter post is just what it says on the envelope containing crucial for transport. The envelope sender corresponds to the sender, the envelope To the receiver. As with the letter - post informs the sender on the envelope ( envelope sender ), if his message was undeliverable - regardless of the sender in the message itself (Body From: header) is called. Non-delivery messages ( bounce messages ) are sent with an empty envelope sender (<>) to prevent email loops.

If the e- mail saved in mbox format, the envelope sender is included in the first line of the e -mail.

For example, if an email sent to the following SMTP commands:

Envelope-from [email protected] Wed June 22 13:49:30 2005 The envelope sender is not normally displayed by E -mail programs, but may by special functions ( ... eg showHeader, show raw) be made visible. As with a letter, you can also specify a false sender, so you should never rely on this information. Only on Envelope-To can be relied upon, as long as the own mail server has not been manipulated, because would Envelope-To previously been tampered with, the email would not arrive.