A follow-up to XP Clients lose WINS registrations
I have now run wireshark on an XP workstation as the problem occurs. A request for "foo" goes to the AD server which responds with "Requested name does not exist" yet on the AD server itself it can resolve "foo" just fine.
Unsure what to do next. It's clearly a problem on the Win2k3 SBS box but I'm not a Windows admin guy :-(