missing XP taskbar/desktop icons

Hi, my brothers XP Home PC is all of a sudden missing it's desktop icons and taskbar - the blank desktop appears but nothing else. The machine doesn't hang - you can still CTRL-ALT-DEL and get the task manager up and launch programs. I've launched explorer which, when I've seen this happen before, seems to 'flush' the system and get it going again - although not on this pc. It's as if it is getting confused in the last part of the startup process - maybe something to do with his user profile - perhaps it has got corrupt or something? any ideas? regards Joel Hughes www.jojet.com - web design and development