network.exe

Good day to all,
I have a small network with a single domain, suddenly no client could access any other client or server or even the DC on the network, when trying they receice a messege like no permissions and access denide even though permissions are granted properly and never changed.
I recieve notification from symantec antivirus that there is a threat "network.exe" i tried to delete the file which is found in system32\wins, but access was denied although i was logged on as domain administrator.
I need your help plz

Thanks

Links:

http://www.google.com/search?hl=en&q=network.exe
http://www.sophos.com/security/analyses/w32rbotarz.html
http://vil.nai.com/vil/Content/v_98561.htm