I think this is a bug in that got into the windows explorer program as I cannot get older "restore" points. ONLY MY CHROME BROWSER WORKS ON PUBLIC WIFI. It also changed my 4935 wifi adapter info by one number on the transmit/receive DNS.
Help and support on WIN xp showed this... but all the GEEKS at Microsoft couldn't figure it out. Still working to resolve it by using another program's (non MS) restore point BEWARE ALL !!!