My new Windows 7 64bit Ultimate system can't see (in file explorer) any computers in my "yorklan" workgroup and none of the other computers can see the new Windows 7 system either. The Windows 7 system also can't see printers in the workgroup.
The computers name is "arizonahp" which is the same name the machine had when it had Vista installed. The rounter can see everybody.
The windows 7 computer can ping by machine name and that works fine and the other computers can also ping the windows 7 computer by machine name. File explorer just can see anything and therefore drives can't be mapped.