I did a clean install of XP one month ago and activated it on the same day. Today, after 30 days, when I switched on the computer and clicked on my user name, I got this notification with the following message:\n"This copy of Windows must be activated with Microsoft before you can log on. Do you want to activate now"\nI clicked on "Yes" and after a delay of about 10 seconds, the Widows Product Activation window opened with the message:\n"Windows is already activated. Click OK to exit"\nWhen I click OK, it goes back to the earlier message to 'activate windows' and then says it is 'already activated. I am unable to get past this loop and unable to log on.