Screen Scrolling Problem?

For a couple of months I've had a problem with my screen scrolling or jumping by itself when I've been using Outlook Express, Word, Excel or when I've been web browsing.

I've tried just about every program to scan for spyware, malware and viruses but they all keep coming up clean so I don't think there is any infection.

I've also uninstalled and reinstalled Microsoft Office and checked all the connections to my PC for the monitor, mouse, keyboard etc with no obvious problems being found.

The problem occurs whether or not I'm connected to the web. Other applications seem to be free from the problem.

Can anyone help please?

Try updating your video card drivers.

Thanks for the suggestion but the problem still remains. Any other thoughts?

Have you tried changing your mouse ? A bad mouse could be causing what you describe.

Having had another go at cleaning my mouse I must say that after a day of testing, the screen scrolling has reduced although it still suffers the odd jump or two. Nothing like before though when the screen would scroll from top to bottom and partly back up at great speed.

Perhaps the mouse was (is) the problem although I still don't understand why it only affected a few applications.

Anyway thank you for your help - much appreciated.