Windows Updates Keep Repeating The Same Update

I have a strange problem. Windows tells me "updates are ready to be installed". This is the update-Microsoft Security Bulletin MS07-042 - Critical Vulnerability in Microsoft XML Core Services Could Allow Remote Code Execution (936227). I have installed this update at least 5-6 times in the last 2 days. I have just realized that this is the same update. I install, and 3 minutes later the icon is back telling me to install-Microsoft Security Bulletin MS07-042 - Critical Vulnerability in Microsoft XML Core Services Could Allow Remote Code Execution (936227). I have restarted the computer after each install, but this has not solved the problem.I am running XP PRO/SP2. I don't know if this has anything to do with my problem, but i recently activated Outlook 2003.