It’s not clear how widespread this problem is, but there are reports that a Critical Update posted by Microsoft last week can cause Windows XP systems to slow down dramatically. Don’t fix this if it’s not a problem, but if you installed an update last week and you’ve noticed a significant change in the way your system is performing, go to Control Panel / Add-Remove Programs and uninstall Windows XP Hotfix 811493. Here’s an article with a bit more information.
