See this post -
http://social.microsoft.com/Forums/en-US/onecaregeneral/thread/93ef4afe-d676-4e5f-bbc8-c9ef06295898I had a sticky about Windows 7, but it appears to have rolled off.
OneCare will not be updated any longer. For Windows 7, you can installed Microsoft Security Essentials which is the free replacement for OneCare antivirus without the extras of OneCare.
http://www.microsoft.com/security_essentials/-steve
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