Exchange 2003 Strange Email Problem
Been having a bit of a nightmare with our Exchange 2003 server. The story begins like this:
Over the last couple of weeks some emails sent to external recipients have not been arriving, not all of them just some randomly it seems.
When checking the exchange message tracking, it tells me that the message has been transferred to the appropriate server via SMTP.
So I thought I do some more checking to make sure, ran smtpdiag on the server, that came back all ok. Ran the online exchange connectivity tester, that was all ok. Ran a check to make sure our server wasn't blacklisted, nope that was fine too.
As a last resort I rebooted the server last night. When I came in the next morning I was greeted by several people asking why they had lots of NDR message's, some of them dating back to November. To my surprise the messages that the message tracking had told me were delivered had actually not been delivered! When I checked the message tracking again, the results contained some extra lines with yesterdays date duplicating the sending process again with a NDR at the end!
My questions are:
Does anyone have an idea what happened?
Why did the message tracking lie?
Is the any method to guarantee a notification to whether a message has been delivered or not as NDR's did not work on this occasion.