try these:
if on static IP, set "Enable NetBIOS over TCP/IP"
if on DHCP, enable "Use NetBIOS setting from the DHCP server"
turn off the firewall if one is running
check Computer Browser Service is started
--
on your PC, set this to YES
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Browser\Parameters\MaintainServerList
and on any other PC's set to NO
--
check workgroup name is same on all PC's
Try installing NetBEUI on all PC's - yuk...
what number does this key have ?
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netbt\Parameters\DhcpNodeType