Just a thought. If your neighbor installed Windows XP SP2, that causes a lot of different brands of wireless cards to disconnect from the Internet. And since everything else works, it might be the SP2. Microsoft advices to uninstall Hotfix Q815485, but I had only a total SP2 install showing in de add/remove programs. I tried a different wireless card and that worked for me.
Here is the deal with a neighbor's system. Cable internet, Network Everywhere Wireless Router, Network Everywhere Wireless Card, Windows XP, Sony Laptop.
He calls one day and says that he cannot connect to the internet. I go over and reset the cable modem and the router, reboot the computer, but still no internet connection. The cable company has verified that the connection is good. The modem has block sync and the router and the modem are communicating. The wireless card connects to the wireless router and the signal strength is high, but I cannot access the internet. All firewalls and uneeded programs have been shut down.
Any ideas? Thank in advance. Fred