Can't connect to Internet even though you have a signal and everyone else is connecting fine.
After doing the whole scanning for critters, updates and installing a new Anti-Virus that wasn't expired I was still stumped. After rebooting the Vista Network Location would default right back to public, which only gave me local access. So my next step was to un-install the wifi drivers and re-install. Worked beautifully and now the default it private and they can access the Internet.
You may need to also reset all the security settings to their default values. I did this afterwards just to be sure I knocked it all out.
http://support.microsoft.com/kb/313222
Also, You will want to make sure you have no malware or viruses and everything is up to date if you have not already done so.
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