Handling undelivered emails in webapp

Question

We have a typical business web app that allows our users to send e-mails with offerings to their clients. We set user e-mail in FROM field so the client can reply directly t

Answer 1

There are 3 "Headers" that emails have.

1. From.
   • This is what the user sees as the 'originator'
2. Reply-to.
   • This is where an email gets sent if a reply is intented
3. Return-path.
   • This is where an email gets routed in the event that the destination does not exist.

You probably want to be setting the 3rd :)

( Note, some servers don't reply to these lost messages at all, becuase recently spammers have been putting addresses there that are not their own, doing a 3rd part bounce attack using the automated reply system to turn email servers into an open relay! )

See Section 4.4 of this document for further details: http://www.faqs.org/rfcs/rfc822.html