Why can’t I login to the domain using XPpro?

I have an XPpro box on a w2k server domain. I had to disable 4 system drive mappings in order to give the client access to a network resource which required one of the drive letters used by the system. I mapped the resource, and was unable to login to the domain. I re-enabled the drives I had disabled, but still couldn’t login.

I can ping the XP box, and access resources logged in as Adminstrator, so the nic is ok, but Active Directory login fails.

I haven’t tried deleting the mappings I added because I need them.

What are the 4 external drive mappings in XP all about?