I seem to have problems similar to that without even touching the mouse the cursor is jumping around, it took about 10 attempts to change the title on a bookmark because it kept leaving the dialog, but was really bad a few minutes ago, my virus scan program had just started, so put it on pause.

Then there is the more obvious, can type and it keeps typing all over the place because of the mouse pad on laptop. I use a separate mouse but sometimes I turn the mousepad back on and forget that I did that.

But I have had trouble lately where mouse moves around the screen so much that I can't click on something.

Another problem with optical mouse is having a hair next to the sensor, vacuum cleaner can fix that or clean with a Q-tip (cotton swab) slightly moist with alcohol. Turn mouse off before looking at bottom -- seems to work better now so that may have taken care of that problem, even though I could not see anything there. Good luck with your problem.

Actually I have instructions here: http://dmcritchie.mvps.org/excel/mouse.txt

Thanks for your help. However, I think what I'm experiencing has to do with disabling add ons-I had this problem before and someone told me how to disable them and then I didn't have any more problems, but I got my computer back from the shop recently, had to get a new hard drive so whatever setting I had it on was erased. I tried doing it myself in the Tools menu but it didn't work. Weird, it didn't jump around while I was typing this-do I need to talk to my ISP?