Take the ball out of the handset and clean the inside and the ball. It really does get dirty in there.

It that doesn't work I would just go buy an $8 new mouse.

I would visit the Logitech web site and download the latest drivers and install those.

Or you could go into your control panel and find the mouse to try adjusting the settings.

michael-
If this is a laser mouse, it would not have a ball. The times I have had problems like you describe is when I am using my laser mouse on hard to read surfaces. One of those is my glass coffee table, and another is my steel desk, which is painted a black semi-gloss. How does this mouse perform when you put it on something like a mouse pad or just a magazine?

If this doesn't help, then: 1) Go into the Control Panel and change the settings for the mouse; or 2) examine the hole on the bottom of the mouse to see if there is any debris or gunk in there. If there is, be very careful removing it as it is easy to mess up the laser optics.

If all this fails, and presuming you have the correct and most current driver, then I would begin to think that it is defective.

Please report back after you have tried all the fixes listed in the replies here.

I want to thank all of you for helping with this frustrating mouse. I did download the latest driver after I read your suggestions and while I did this I got into a live chat with one of their techs and he personally called me and told me to NOT use a mouse pad. He was absolutely correct because with an optical mouse the light bounces back into the mouse and confuses it.I just threw the pad aside while on the phone and the cursor is working perfectly.This was a $40 mouse and I didn't feel I should buy another. Thank all of you again. Michael

Hmm, nice that Logitech have the live chat techs and you got to chat and sort the issue out. Hopefully there was no fee or credit card number handed over?

There was no charge although he tried selling me programs to speed up the computer, I declined.

Most mice are neutered now...

I have much better luck with a plain white mousepad. Had a black one and I finally figured out that was causing me all the trouble.

I just like the feel of a mouse pad better than right on the desk.

I have a medium gray mouse pad and use a Logitech wireless laser mouse. It works perfectly. I started using this because my desk finish was getting marred by my moving the mouse around on it. The desk is also a medium gray finish. I know that a laser mouse will not work on all surfaces, however.

Use any rigid base to operate the mouse and kindly check your settings in control panel.

Your note made me smile - at myself. I have an optical wired mouse on a wooden table. Going back a ways the cursor began jerking all over the screen. The time coincided when I was doing something with AVG, I think. I went through a variety of stuff with them but no luck. About the time I was ready to get another mouse I found a small piece of dust bunny that had embedded itself into the mouse's light receptacle. Removing it cleared up the problem. It was embarassing to call AVG and fess up, but I did. Thanks for bringing on the smile. Gene