I have a Dell Latitute laptop running Windows 2000 (version 5.0 SP 2).
When I use the touch pad the cursor frequently moves as I am typing, jumping up a line or more and left or right with no discernable pattern. This does not happen when I attach a mouse, but I prefer the touchpad and use it most of the time. I am also careful not to allow clothing or things to drag across the pad. The problem is intermittent, some days it is much worse than others. (So far it has not happened while typing this message.)
I had the same problem with another Dell laptop running Win 95, and on this laptop when it had Win98. It is most noticeable when doing email
(IE) but happens also in MS Word.
