[newbe]

I'm running Windows Vista Home Premium on a laptop thats about 18 months old and I've had no serious problems with before. But now, when I log off, shut down, restart etc. it gets stuck on the 'logging off...' screen, but not frozen as the little...

I'm running Windows Vista Home Premium on a laptop thats about 18 months old and I've had no serious problems with before.

But now, when I log off, shut down, restart etc. it gets stuck on the 'logging off...' screen, but not frozen as the little blue circle continues to spin. I've tried leaving it for about 30 minutes, but nothing changes.

Similarly, when I start up, 9 times out of 10 it reaches the 'Welcome' screen but then cuts to a plain blue screen with the cursor still visible and active. Even when I've tried safe mode, it comes up with a black screen with safe mode in the corners and nothing else. As with the log-off screen, it does nothing even when left for 30+ minutes.

I haven't (as far as I'm aware) added or removed anything important recently and I've tried running a couple of up-to-date virus scans, but they came up with nothing. Similarly, I've run RegCure and CCleaner and found nothing.

Any suggestions/help would be hugely appreciated.

Thanks...