Catching a Email Loop from a out of office agent

Question

Our Current email2fax gateway does not handle bounced emails very well. When a email is sent to the gateway the content is faxed out and a notification is sent to the original sender of the message.

Problems happen when the original user turns on a out of office agent and messages will bounces between the 2 email gateways.

I have tried to set in the outbound notification the following headers

From Reply-To

But as this is a proprietary gateway it does not allow me to set a custom Return-PATH some silly mail servers send replies back to that.

Are there any extra email headers that maybe I could set to say "Do not send a Notification back"

If not is there a email gateway that would be able to act like a proxy and sit in front of the gateway that would then allow me to programmable check the messages as they came in and drop out of office messages.

Answer 1

I would have thought an anti-spam program like SpamAssassin could be fine-tuned to catch out-of-office replies.

If your mail gateway can't even have an anti-spam system plugged into it then it really is a bad system to have around!

Answer 2

Try setting the Precedence: bulk-header (or junk) in your notifications. Usually OOO-notifiers like Unix vacation do not send notifications for incoming mails with that header.

As this header is slightly discouraged, you could try setting an empty Return-Path, as suggested in http://stackoverflow.com/questions/154718/precedence-header-in-email.