I have a bunch of computers in a remote office along with a BDC in that office. They are on a different subnet from the PDC and across a much slower connection. But for some reason if the network between them is down, none of those computers can login. They can get to the machine no problem because all of their files are stored there. How do I tell which DC a computer will log in to, and how do I force a change if it's using the wrong one?