Hi,
When we did our migration from Groupwise to Exchange 2013 we initially started with a testing domain (ad.domain.com) to start migrating to. After some accounts were migrated to this test domain and we did some other testing, we changed the accepted domain from our test to our production domain (domain.com). A few days later we noticed some issues with some users sending email to other internal users and it appeared they were sending to the test domain which was being bounced back as its no longer an accepted domain. We do not want it to be an accepted domain as it was only for testing. We then noticed every user had 2 SMTP addresses listed so we removed the one that had the testing domain and left the correct one.
Our primary issue now is that users RecipientCache for the OWA is constantly populating itself with these invalid addresses as it must be scanning emails in their mailbox that have the bad domain used. We can use a script to clear the bad domain from
the recipientcache but its only a temporary solution. There does not appear to be an issue when using the Outlook client just in the OWA.
We were able to verify that the emails that were migrated from groupwise before either the SMTP change or the accepted domain change all appear to have the testing domain and the correct domain on the users listed in the messages.
Also to make things more confusing the testing domain that we used was the same as our actual AD domain that Exchange is connected to (ad.domain.com).
We are using Exchange 2013 CU9 on Windows Server 2012 R2
Thanks in advance,
Matt
