There are 4 computers and a laptop all joined to a switch whitch is connected to an ADSL router in our office.
All computers worked fine with each other and there was no problem, then we attached an access point to the switch and changed laptop connection to use wireless to have more portability.
From then on the laptop couldn't find any computer in the workgroup anymore, still all the network connections work fine, I mean, the laptop can use internet and can ping and even browse other computers via IP address.
No computers appear in the workgroup except for the laptop itself. Any suggestions?