Vista misinterprets normal shutdown as 'unexpected' - then boots up again.

I downloaded the driver sweeper and used it according to the instructions. Alas, this is one broom that did not sweep clean, as I was still harangued, on startup, by a dialog screen inviting me to register my "new ATI product".

In despair (a familiar emotion since I got to know Vista), I opened up my PC and removed the ATI card, reverting to the on-board Nvidia 6100 graphics. The downside to this being that instead of benefitting from 500Mb of dedicated video memory, I'm now having to share up to 768Mb of the main system's 2Gb of memory.

Anyway, everything now seems back to normal. I get proper shutdowns and no artefacts on screen.

Thanks again Fabler, for your assistance.

I would have replied sooner but for problems logging on to this site. I log in using my usual details, then it goes to a screen saying "Ooops! We couldn't find the page you wanted!" and that's it!

Today I think I got lucky - persistence pays.