Check your computer date and time. If the date and time are set correctly check the status of your subscription at http://billing.microsoft.com by signing in using the Live ID and password associated with your One Care subscription. If your date and time are correct and your subscription status at billing shows 05/2010 expiration please contact support. How to reach support - http://social.microsoft.com/Forums/en-US/onecareinstallandactivate/thread/30400b52-7f26-4ba0-bc18-17e305329d90Jim - MVP Windows Live - Forum Moderator - Live One Care - Live Mesh - Microsoft Security Essentials