I have almost the identical problem as listed here http://www.experts-exchange.com/Operating_Systems/Q_21083952.html
1) cant see/access shared workgroup folders
2)Cant Ping one direction but can ping in the other
1 XP H desktop hardwired to linksys inet ok
1 XP H laptop wireless conn excellent and inet ok
laptop can ping desktop but not vise versa
disabled SP2 firewalls on both
Trying to solve ping problem first because I think that is why XP networking is having a problem.