I have exchange 2013 and 2010 installed and I'm in co-existence mode. Everything is working correctly except OWA. When I login with an account that has been moved to 2013 it works perfect but when I try to login with an account that is still on the 2010 server I get the ":( Sorry, something went wrong" message.
Outlook Anywhere and ActiveSync also works fine to access mailboxes on either server.
Any ideas on what I might be doing wrong?
Thanks!