Try running the virus and spyware repair tool -
http://social.microsoft.com/Forums/en-US/onecareanti-virus/thread/0c3905ab-672e-41c4-9be8-8f0f1636f123 If the issue persists after running the repair tool you can contact support for help. How to reach support -
http://social.microsoft.com/Forums/en-US/onecareinstallandactivate/thread/30400b52-7f26-4ba0-bc18-17e305329d90
Jim
Microsoft MVP Consumer Security - Forum Moderator - Live One Care - Live Mesh - Microsoft Security Essentials