I have already migrated multiple users with no issues, but this last user, once his mailbox had been migrated over to our Exchange 2013 SP1 servers, his Outlook client could no longer find the Exchange server. He received the message that an admin has made changes that require them to restart their Outlook client. Once he did that, he was presented with a message that Exchange was unavailable and that the server may be offline. All other users, who also reside in the same subnet, are working just fine.
He can connect via OWA and his mobile device with no issues, it is literally just Outlook. I logged on to the same machine where he is having the issue and was able to configure my account with no issues. I removed his mail profile and recreated it with no success. I then took it a step further and removed his local computer account and recreated it...still with no success.
I then had him log into a laptop with Outlook 2013 installed and he was presented with the same errors. If I configure his Outlook profile manually, it will work just fine. Also, if I migrate his mailbox back to an Exchange 2010 mailbox database, everything works just fine.
I still have hundreds of mailboxes to migrate and want to make sure this issue is resolved before proceeding. Any information or other troubleshooting steps would be greatly appreciated.