Mouse pointer position changes

[trevor101]

I haven't added any new programmes [or got any viruses/spyware- using Windows defender and AVG free] but my mouse cursor unexpectedly moves to either the top left or bottom right of screen- sometimes whilst I am in the middle of moving it to click on a button. I have checked the control panel and it isn't set to go to the default focus of a dialog box. I have to press the Ctrl key to find where it is.
It is an optical mouse and I have put a piece of white paper on the mat, used no mat, etc.

I have reinstalled the driver and rebooted but no joy. Any suggestions as to what is going on and how to stop it?

 

[SydneyGeek]

My mouse does that too sometimes.

I think it's a feature of being an optical mouse: when you move it, as long as it always stays dead level, all is OK. Sometimes when one edge is slightly raised during mouse movement, off goes the cursor. I assume that the laser reflection comes back in a very different location; the mouse detects that as big movement, and off you go. It's sporadic, so I just live with it.

Denis