Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I recently migrated an Exchange 2007 server to Exchange 2010. After the migration, I accidentally left the MX record pointing to the old Exch 2007 in the domain for an extra day. As the result, some emails might have been directed to the empty old server. The external senders didn't get any undeliverable reports, therefore I assumed the missing emails were "processed" somewhere. Is there any method that I could retrieve those missing emails?

share|improve this question
Is the old server still configured to be authoritative for the domains it received email for? – Coding Gorilla Sep 13 '10 at 19:40
no, the authoritative server for the domain is the Exch 2010 server – wes Sep 14 '10 at 20:05

Depending on how you performed the migration, that Exchange 2007 server may still be in the Exchange infrastructure, and correctly routed those messages to their home on the Exchange 2010 server. This assumes your migration method involved moving mailboxes from the old server to the new server by native Exchange methods, rather than something else. You can check the Transport Logs on the old server to see what it did with those messages.

share|improve this answer
Yes, we moved the mailboxes over the the new server on the same day of migration. I checked the message tracking logs on the old server on the day that old MX record lingered, and some messages were marked "Routing Failed 550 4.4.7 QUEUE.EXPIRED;", even though the original sender never got an ack on failed delivery. What could be doing this? – wes Sep 14 '10 at 19:18

If the old IP accepts connections on port 25, then these emails would have been accepted or bounced by that server, depending on its configuration. If it was not accepting port 25 connections, then the senders are likely still spooling and trying to send the message, so changing your MX record to the new server will cause email to flood in.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.