Hey X-ray, sometimes the icon 'registry' or cache gets corrupted. I've had this happen - sometimes icons get stuffed, sometimes they don't appear at all, etc. Try this:
Just refresh the icon cache by deleting the IconCache.db file from your profile directory (usually /Documents and Settings/Username/Local Settings/Application Data). It will be automatically recreated.
That should fix it. Got that from
hereTry giving it a reboot after doing that and see what happens. Good luck :-)