Posted 16 September 2009 - 10:04 PM
The other 3 PCs have no issues connecting and staying connected? If that is the case then we can eliminate the modem and router from being part of the problem.
Since you did a long list of things and the people over in Virus Land said you were clean that leads me to think its something going on with the network card.
First try this: From a command prompt try this command netsh int ip reset resetlog.txt reboot and see if that fixes it.
If not try this: Open Device manager and get the name of the Network Adapter. Then goto the manufacture's site and download the latest drivers. If its a name brand (Dell or HP) then you could go to their site and look for drivers. Once you have them on the troubled PC, thumb drive are awesome for this sort of stuff, I'd uninstall the adapter from Device manager and look in add/remove programs for anything about the adapter. Reboot and install the new drivers.
Hope this helps
Associate in Applied Science - Network Systems Management - Trident Technical College