the network path was not found

this is my problem:

Domain Controller: Windows 2000 sp4 server
Client Server: Windows 2003 SP2

I am trying to join the windows 2003 server to the Domain and I get this message every time I authenticate, “the network path was not found.”

I already checked a few things already to make sure these were not the problem:
1. NetBois over TCP/IP is enabled and the service is started in the services console.
2. The 2000 server is sharing printers and files over the network.
3. I can ping the Domain Controller and other computers over the network and even the DNS server but just can’t join the domain.

I have not way of logging into the DNS server thats not under my control so what could my problem be?