If you have One Care installed on another computer you can open One Care>Help>About Windows Live One Care and you will see the Live ID associated with your subscription. If you do not have One Care installed on another computer or if you cannot remember the correct password you can contact support for help. How to reach support - http://social.microsoft.com/Forums/en-US/onecareinstallandactivate/thread/30400b52-7f26-4ba0-bc18-17e305329d90
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