I have both Exchange 2010 & Exchange 2013 CU1 installed (co-existing in the same forest).
I have not yet moved all mailboxes from Exchange 2010 database to Exchange 2013, I just moved one mailbox for testing and it migrated successfully but only the OWA is working on that account not the Outlook itself, the Outlook is still pointing to the Exchange 2010 name and giving me disconnection error.
My question, once I migrate all accounts to the new Exchange 2013 database and I uninstall Exchange 2010, will the Outlook clients point to the new server name which should be the Exchange 2013?