I've just set up a new 2008 SBS Server and exchange seems to be working fine internally, and indeed OWA is working fine externally. I'm having a problem however with Outlook Anywhere. When I try and set up an external Outlook client to use Exchange I am adding the remote.domain.co.uk into the proxy settings in Outlook and I am being prompted for username/password but I can't seem to resolve username to internal Exchange domain name. I've tried pretty much all possible combinations of servername/domain/servername servername/domain e.t.c. but whatever I do I can't resolve the username. I've gone to testexchangeconnectivity and run the RPC test and all the steps passed apart from the very last one which says:
SSL mutual authentication with the RPC proxy server is being tested.
Verification of mutual authentication failed.
Can anyone please shed some light as to where I'm going wrong?