[Mimedefang] validating mail was sent from your domain on bounce back messages

[Lucas Albers]

One of my users is getting mail bounced back, that he did not send.
I was determing how to prevent this.
All the mail my users sends is only sent though 1 mail server.
On all outgoing mail, add an X-Header that indicates it was actually sent
though your mail server.
On mail bouncing back, that appears to be sent from one of your users,
look for the X-Header. If it is not their, then reject the mail.

Has anyone else encountered this particular problem or a solution for this
sort of problem?


-- 
Luke Computer Science System Administrator
Security Administrator,College of Engineering
Montana State University-Bozeman,Montana