Win 2000 Pro Network Issues

I’ve a computer with a triple-boot (BeOS/Windows, and then Win98/Win2000). Ignoring the BeOs side, here’s the situation: I can reach my local network from the W98 side, but not the W2000 side. On Win 2000, When I try to add the ws to my local domain, it tells me that the domain doesn’t exist. And yet it’s obviously getting network communication, because I can reach the Internet. Any suggestions?