The NodeType parameter determines the sources and order from which NetBT
attempts to resolve names. Peer-Peer probably indicates P Node, and this
will not work for you unless you have a WINS server on your network. For
most workgroup environments, either B node or H node are the best choices.
See:

http://support.microsoft.com/default...b;en-us;160177

These are the instructions to get access back.

1- Open dos prompt, type ipconfig -all.
2- Look at the 'Node Type' it probably says Peer-Peer or something like unkown .... we want it to say 'Hybrid'
3- Press 'Start' button > Run... > In the box type regedit.
4- Navigate the tree to: HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services/NetBT/Parameters
5- Right mouse click and select New > DWORD Value
6- Name it 'NodeType' (without the quotes)
7- Right mouse click on it and select Modify
8- Set Value Data to '8' (no quotes)
9- Leave Base alone. 'Hexadecimal' should be selected
10- Press 'ok'
11- Close regedit and reboot. (Your done!)
12- Open dos prompt and type ipconfig -all, for node type it should now say 'Hybrid'