This was a bit of a random one today …
I could logon to Outlook Web Access 2007 (thank goodness someone installed Exchange 2007 with the CAS role already installed). But when creating a new Outlook profile, no matter what I did I kept getting an error when doing a Check Name.
I looked at all sorts of options to do with the recipient, permissions, and all that sort of stuff.
Then it struck me… This was all in VMWare, and the “network” connection was not enabled (it was set to not connected, and not to connect on start up).
As soon as this was connected, Outlook worked fine!