In my local network at home network file sharing, RDP, even ping stopped working for one my desktops.
I have ZoneAlarm Pro, Norton Antivirus and many other software installed disabling any of this didnt work. The culprit was Cisco VPN software.
My wife had installed Cisco VPN client software and everything was fine – but this creates a problem for any local network operations coming into the machine even when not connected to the VPN. Solution stop the “Cisco Systems, Inc. VPN Service” and everything works fine.
[The version of the Cisco VPN client is 4.8.02, this ]I dont know if there is an update for the software with the fix but for now I have changed the startup mode of the service from automatic to manual. This works for me since the sharing will be a problem only when connected to the VPN and for now this rarely happens.
(I found a blog post related to the same issue on http://wiki.helpware.net)