I have now moved everything from our sendmail server to the development Zimbra server. I am now getting emails back from several domains that have in the return message.
Reporting-MTA: dns; mailhost.intdoc.com
X-Postfix-Sender: rfc822; firstname.lastname@example.org
Arrival-Date: Wed, 1 Mar 2006 18:20:57 -0600 (CST)
Final-Recipient: rfc822; email@example.com
Diagnostic-Code: X-Postfix; casham.com: Name or service not known
The domains listed are "real."
Where should I start? I looked for similar problems on the forums but didn't see anything that fit. I have used Sendmail but am not familiar with Postfix.
I am using 3.01 (160) on RHES 4