I have a Win2000 network with a parent and child domain. The domain is using active directory and seems fully functional EXCEPT members of the child domain usually don't get their password validated until the second or third attempt at logging on. The error reads 'The domain password you supplied is not correct, or access to your logon server has been denied' - neither of which is true. The error comes back almost instantly - like not enough time has passed to really check. The child domain has 3 servers and the validating servers sit on the same switch so it isn't the physical network. The parent domain has no problems.
I have no idea where to start tracking down the problem.