I am having a major headache trying to troubleshoot this issue.
My environment has an exchange 2010 server installed and running fine. We just installed Exchange 2013 in a coexistence situation (after upgrading 2010 to the SP3 RU5 etc) and migrated a few test mailboxes (mine included) before we do the full migration.
Setting up Outlook happens correctly. Autodiscover works and it resolves the name of the mailbox automatically and I get the correct guid@domain.fqdn (cant post images until im verified)
If I have to manually set up a mailbox (manual exchange connection) if I type in exch2010.fqdn it resolves to the mailbox correctly no matter which server or database it resides on.
|If I type in exch2013.fqdn I get the following error (action cannot be completed, the connection to Microsoft exchange is unavailable)
The only way to resolve this is to edit the registry HKCU\Microsoft\Exchange\Exchange Provider and add a string DS Server and point it to either of our 2 DCs (both are GCs). Doing so allows me to enter the exchange2013 fqdn and it resolves but not to the GUID but to the fqdn of the server.
Troubleshooting
I have spent days (if not weeks) trying to figure out why this is happening. DCDIAG gives me perfect results, DNS has been cleared of all the old name servers (there were still pointers of very old DCs showing as name servers in a few places but that has been thoroughly cleaned. replication is working fine, I have scoured event viewer of both DCs and both exchange servers and nothing stands out as relating to any errors.
Reason I need this resolved
The main reason for needing this resolved is that our ArchiveManager (mail archiver) is unable to log into any of the mailboxes on the new Exchange 2013 server (needs to do so in order to sort through the mail within each mailbox). There is no problem when
accessing any mailbox on the 2010 server.