Cannot create new outlook profile

Back again,

I can't create new outlook profiles using the cas array name, i get

"the action cannot be completed. the connection to microsoft exchange is unavailable"

However, if I use one of the cas server names, I'm fine

I have ports 80, 110, 135, 443 opened, my users are using https over RPC as a connection. I can connect just fine to outlook on machines with currently existing profiles.

I'm reading alot of people set static ports for RPC, I'd rather not do this at this point.