My wireless Optical mouse 2000 Scroll wheel works intermittently-- "the mouse sigal is low"

Excellent suggestion Morf1961!  Removing the peg that causes the ratchet feel while scrolling resolved all problems, and the scrolling wheels turns much better now! Everything works smoothly, I cannot believe Microsoft didn't notice this problem during testing. I removed the peg completly using pliers, but be careful not to distort the brackets that hold the scrolling mechanism.

Andrea, glad the wheel mod worked for you. I might well cut the peg out on mine as well, but I don't want to do that until I'm sure the scrolling is fixed.

Meanwhile, the scrolling saga continues...

Having been away all week, and used my mouse for the first time tonight, the scroll still didn't feel quite right, it was still skipping occasionally.

The screw was as loose as it could be without the case rattling, so I thought I'd try and work out what effect the loose or tight screw was having.

As I mentioned above, the scrolling mechanism itself is worked by a "star wheel" which turns in between an (I guess) infrared LED and a light sensor. As the pins of the wheel break the light beam this is sensed as the wheel turning.

To cut a long story short, my experiments brought me to the conclusion that the problem is that the wheel sits slightly too low in between the light and sensor, so that sometimes the light is shining on the hub of the wheel and so the beam doesn't get to the sensor.

This would explain why the case screw being too tight causes a problem if it pushes the wheel downwards.

The height of the wheel is determined by a tab at the back of the wheel which presses down onto a microswitch to work the "middle mouse button" press. The wheel is hinged at the front and lifts up easily.

What I did was to add small pieces of paper - I used a post-it note so they stuck there - one one top of the other to build up a stack and thicken the tab, hence lifting the wheel. I think I used about 6 or 8 pieces in the end to make the mechanism work well. You can keep the batteries in the mouse while you are doing this so you can test it.

Once I was happy with the height, I tidied the stack by trimming the edges then taped it in place and reassembled the mouse.

It's feeling better still this time, seems to be scrolling very smoothly. The "middle mouse" click is a bit "sudden" now, but I hardly ever use this so it doesn't trouble me.

I'll give it a few days and see if it carries on working, if I have any more problems I'll report back - watch this space!

If you have to loosen a screw to make it work, ICROSOFT? Dont you have anyone testing before you sell it? I mean if everyones mouses scroll wheel is broken and fixed by a randam half-screw turn, Dont you think it should have shown up in product testing. Thats Micrsoft for ya, .... btw, I had to turn the screw a full turn loose and my scroll wheel works for the most part, it occasionally still jerks up when scrolling down or vice-versa but its doing it 90% less now.... its actually usable now.

Hi Morf1961,

I tried your trick and the scrolling seems much better now. Instead of using pieces of paper I just wrapped some sticky tape around the tab that presses onto the middle-button switch. I cut off the excess tape that exceeds the length of the tab with a pair of scissors. It's quite easy to regulate the thickness that you need to improve the scrolling, but you really don't need that much to fix the scrolling. It's working perfectly now.