There is an annoying little issue with Win2k AD that I come across from time to time. You can't map remote drives twice.... Sounds silly but take a look and see that the device isn't being mapped by both a login script and by explorer itself. The second one messes the system up and IIRC there is no Event log entry for the failure. Security wise I can see it as an advantage, netadmin-wise it can be a bugger to work out.....

Hope that helps....