I have Exchange 2010 SP3 (two CAS, two mailbox servers) coexisting with Exchange 2013 CU2 (two CAS, two mailbox servers). I have not yet committed DNS changes to point clients to the new Exchange 2013 CAS servers. I want to verify my clients will be able to connect to their mailboxes before finalizing the cut over. I have migrated ONE user account. Mail flow works fine between Exchange 2010 users and the Exchange 2013 user. OWA works fine for the migrated user. However, I can't seem to connect Outlook 2010 (fully patched) or Outlook 2013 (with patches) directly to the migrated mailbox by BYPASSING the CAS. Since DNS has not been adjusted, autodiscover is still pointing to Exchange 2010.
The workstation is a domain member, the migrated user is not hidden in the address book. Internal Outlook authentication is set for NTLM, but I'm not sure that even matters if I'm bypassing the CAS.
I am configuring the connection manually. I enter the server name of the mailbox server hosting the migrated mailbox and the full name of the user. Errors reported by Outlook include:
"Outlook cannot log on. Verify you are connected tot he network and are using the proper server and mailbox name. The connection to Microsoft Exchange is unavailable. Outlook must be online or connected to complete this action."
and
"The name cannot be resolved. The action cannot be completed."
I have seen countless posts related to these messages, but most are related to Outlook Anywhere configuration problems; problems I believe are fixed by modifying CAS server configurations.
I don't know what logs I should be looking at on the mailbox server I'm attempting to attach to.