Turns out it was interference with the IPv6 address. Disabling the IPv6 solved the problem
Using a HP dv9700 laptop Vista Home premium. The wifi has been working fine until today. I attempted the ad-hoc feature to link with my Linux box and nothing happened. Shut down the HP went about my day. Later when my sister tried to access the web it told her it was unable to connect to the network. Now we share an access point with our neighbors and have never established a password. My Linux PC is on-line just fine and the neighbors have no issue with their connection. My sister's HP will detect the network but wont connect I disabled the ad-hoc feature using the elevated command line assuming Windows was trying to connect through that still, I removed the ad-hoc network from the list. We have run the setup wizard several times but it always comes back to the list of available networks and wont connect. The HP cant ping the router and has no IP address anymore. I assume that is a given considering it can't connect.NIc is a broadcom 4321AG 802.11a/b/g/draft-n wifi adapter

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