I have a 2003 SBS running as my Exchange server. I had something new come up yesterday. One individual sent out several emails on Feb 22 and Feb 23 that were important and time critical. On March 9 she received NDRs for two of them. I am trying to find out why there was such a delay between sending and NDR.
Using ESM I went to the properties of the default SMTP Virtual Server and I have outbound delivery with defaults of retrying every 10 minutes for the first 3 times and then every 15 minutes thereafter with an expiration timeout of 2 days. I have changed the expiration timeout to 1 day. When I went to message history I could see the message routed and queued for remote delivery at 2:13 on Feb 23, again at 2:15, then at 2:28 and again at 2:31. The next entry was on 3/7 15 10:38 AM. The next entry after that was on 3/8 at 8:25 PM and it ended with a NDR generated. The domain the message was sent to does not exist. It was sent to XX@omahatriahtlon.com when it should have been sent to XX@omahatriathlon.com. There was a transposition of the "TH" so the domain was not found. I do not understand why the document stayed there that long before generating the NDR. We usually get the NDR for a non-existent domain immediately.
After I found out about this yesterday I went to the print queue and I see documents to 3 different recipients that are sitting there. On 2 of them I have verified that the domain does not exist.
This is a picture of message history on one of the items. The domain should have been @creighton.com but was mistyped as creigthton.com with an extra "T". This was sent on 3/9 and today is 3/10 but it is only showing the item being submitted to the queue one time.
I just checked recent NDRs to see if I could see a pattern. On 3/8, after receiving an NDR for the email sent out on 2/23 our user tried to resend to the same domain. 25 hours later she got an NDR because the domain was misspelled. She has since corrected the address and the email has been delivered. But I do not understand why some NDRs are being generated and others are not. I am used to seeing an NDR for non-existent domains being generated within minutes, not days. What should I look for to fix this problem? Until it is fixed I will be checking the queues every day.