Same issue here. There were two copies of the update manager, I deleted one and it seemed to resolve the issue. I have an XPS M140 and I wonder if the issue has something to do with the fact I had them update me from XP Media Edition to XP Pro?
I can only guess it happened when the set up the XP Pro.Support didn't seem concerned about it.
Same problem as this 2005 post. What do I do to stop this annoying loop? Are there updates that I need to install?