We are moving from Exchange 2003 to Exchange 2010 and have a ISA 2006 as a firewall. Autodiscover and Activesync tests are working from outside. When I try to add a new profile to connect using Outlook 2010 I get error - Cannot open your default email folder. I am able to login to OWA without any issues. Same thing with the Android/iPhones I am able to setup the account using autodiscover but then get error - "Cannot get mail. Connection to server failed"