Ok, strange problem (to me anyway)
I have a new client that has existing infrastructure.
The DC is a 2008 Server R2 64-bit. They are also running Exchange 2010 and a HyperV terminal server.
I was asked today to create a new user and email for a new employee. Ok, no problem. However, when I arrived to set the user up on their computer I discovered she had a notebook running Tablet PC OS. When I tried to log her on the the tablet I received an error message "unable to log on because the domain not available". That is not the precise message, but close from memory.
The tablet is joined to the domain.
The tablet has existing users that can log on.
The domain admin can logon to the tablet.
The new user I created can log onto any Win XP PRo workstation in the domain.
If you try to logon a user that doesn't exist in the domain, you receive the same error message.
There are at least 5 tablet PC's at the site, and the new user can not logon to any of them.
Most existing users in the domain can't logon either, just some. (same error)
The new user is a member of the same groups as the users that work.
Even making the new user a domain admin did not work.