The Envelope-Sender address is the email address that identifies where the email originated. It is also the address to which any undeliverable message notices, or bounces, are sent. The Envelope-Sender address is also referred to as the Return-Path address, the Mail From (MFrom) address, and the bounce address.

What is the envelope sender header?

The envelope headers are the MAIL FROM and RCPT TO parts of the SMTP conversation. The envelope sender is the MAIL FROM address, and the envelope recipients are the RCPT TO addresses.

What is sender's address?

What is a Sender Address? ... Usually, a sender address is always a business email address and reflects the “From” part of an email creations so that the recipient can identify the sender of the email.