I recently migrated external users that connect to my org across the Internet from Exchange 2010 to Exchange 2013. In Exchange 2010, I had a CAS Array called outlook.DOMAIN.com and these external users had this defined as the Exchange Server in their Outlook Anywhere profiles (of course in the proxy settings they had my Internet-facing CAS server defined - owa.DOMAIN.com).
Post-migration the users are unable to connect to Exchange when launching Outlook. The only solution I have found thus far is to have them repair their Outlook profile and grab the new settings via Autodiscover (outlook.DOMAIN.com is now replaced with a long GUID in the Exchange Server portion of the mail profile).
My question: Is there some configuration that allows these external users to get the new settings when attempting to connect to that old CAS Array name, or is the only solution to have everyone repair their profiles?