Topology and setup
We have main office A, and branch office (abroad) B. Our ISP somehow messed up the MPLS, and office A<>B will not be connected until a few days. At location B, we have an AD (and the other two ADs at location A). Location A also have an exchange server.

The problems
A few users at A have problem to login to their computers running Windows XP, the logon process kind of hangs where "Applying computer policies". Additionally, I can't start the Exchange management shell, it fails on get-recipient because the AD abroad (location B) is unreachable.

Solution?
I could delete the AD at B, but Im pretty sure it will be a hazzle to re-join it, and since the office is abroad it's not an option to just go there and re-install it -> re join, I now wonder how I in location As primary and secondary ADs can temporarily disable AD at location B.