I forgot who has been recommending it but I've been running SetiHide on one of my rigs for several weeks now and it is really smooth.
I wouldn't recommend one over the other but if you are having some issues with SetiDriver you could:
1. Delete it completely and start over with a new install of SetiDriver
2. Delete it completely and start over with a new install using SetiHide
The two programs do the same primary thing, cache WUs, but SetiHide does allow you to run it on a computer without any icon showing up in the startup tray (hence its name). I'm looking forward to the next version which is supposed to have the additional feature of installing it as a service for Win2000/XP.
I don't have a clue about your current problem but just wanted to give you a couple of alternative ideas.
