not able to attach to domain

i have a windows 2000 professional and i need to connect it to the Domain and the server is Windows 2000 advanced server
when i try to connect the workstation to the server for domain it says “the following error occured attempting to join the domain “wtnpl” The network location cannot be reached.
but i am able to see all the sytems in the network.
but when i tried to connect to NT4 server i am able to connect it and i have also updated the latest servive pack