If it's not a Mcafee issue:
Look in add/remove to see what updates it thinks are on there (which they probably aren't fully) and delete, reboot. If still blank pages try deleting/reverting ie also and rebooting. If ok go to M$ windows update and 'scan' for updates.
BTW there's been many conflicts with xp and updates. One way is to delete 'updater' and reinstall from M$.