I love the scroll wheel on top of the Apple mighty mouse, but after a while the sweat and oil on your finger combined with grit and dust clogs the whole thing up. This manifests itself in the scroll wheel not scrolling down, or up, or in worst cases, not scrolling all. Here’s how to fix the problem.
I rang Apple and said my scroll wheel was not working and they gave me this simple but effective solution over the phone.
Simply take a sheet of clean white paper, put it on top of the mouse, and press down on the scroll wheel with your finger, but with the paper between your finger and the scroll wheel. Press quite hard with it and at the same time scroll around – moving it up and down and round and round. Move to a different area of the paper and give it another go.
The paper seems to absorb all the oil and gunk off the scroll wheel, and the scroll wheel in turn when it is clean must absorb the gunk off the sensors or whatever is underneath it.
I have found that a better method, especially with a dirty mouse, is to turn the mouse upside down and run the scroll-wheel in circles on a clean piece of paper until all the dirt comes off.
Make sure you use a brand new clean piece of paper.
Do not use alcohol. The rubber scroll wheel is sensitive and the alcohol is not needed.
No not use water. You don’t want water getting into the inside of your mouse!
It’s just dirty. It’s funny that I could not find this information anywhere on Google or on the Apple web page.
This clean paper trick works amazingly well.