Persist header data across reply emails

Question

Am trying to determine the best way to persist information from an originating email, through to a reply back.

Essentially, it is to pass a GUID from the original email (c#), whereby when the receiver replies back, that GUID is also sent back for reference.

I have tried setting the MessageID, whereby using Outlook, the In-Reply-To value is set with the original ID, however using some webclient email systems, that value is not created on reply. Is there another way to sent this info through email headers?

Answer 1

Some variation on VERP is probably the most reliable...

http://en.wikipedia.org/wiki/Variable_envelope_return_path

Specifically, instead of having all your replies coming to the same address, encode the information you want to persist into the From address for the email.

For example, in the case of a helpdesk ticket, you could use something like:

From: Helpdesk <[email protected]>
To: End User <[email protected]>
Subject: Ticket #123 - problem with computer.

That way, regardless of what the user edits in the subject or text, you know what ticket is being referred to by the receiving email address.