Excessive network traffic from workstation on W2000 Domain

Here's an interesting situation thats got me stumped:

To facilitate the move of two employees, I physically switched the location of their Win98 workstations on our W2000 server domain. Prior to the move, both employees worked on their workstations, and everything was fine. After the move, one of the workstations, as soon as it started up, generated so much traffic on the LAN that no one could access the server. Even the offending workstation itself could not see the domain controller to log on.

Note that just moments before, in its previous location, this was not an issue.

To eliminate faulty wiring or some other hardware issue, I hooked up another workstation in this same location. No problem.

I checked the workstation for spyware, viruses, and programs running at startup that might communicate with the network. I removed what little spyware there was, there were no viruses or unecessary programs running at startup.

Any ideas? I thought about the network card, but it was working fine just moments before, and shows no indications of a problem.

Thanks,
Bill