I recently migrated a company to a Microsoft domain environment, logged the users in under their new domain accounts, and then copied the old profiles to the new profile.

I am not sure if that is related since they did not complain about it right away and it may have been a subsequent patch or something, but I have two XP computers that will not open IE8. You click on it, and it nothing graphically happens at all, but you can see a process in task manager. If you click many times, you get multiple instances. It will appear often TWICE per click. It still works in the old profile, so it is specific to the profile, and I would like to fix it rather than blow it away.

Here is what I have done without success: Tried opening without add-ons (the one in System Tools)
Reinstalled IE8
Ran SFC /SCANNOW
I found a script that was supposed to repair any registry entries, and ran it.
I tried exporting the whole HKCU\Software\Microsoft\Internet Explorer key and deleting it, hoping that when I restarted it, it would recreate it...No joy. I restored it.

Any ideas?