Problem scenario
Your mouse scrolls up when you use the scroll wheel to scroll down. What should you do?
Solution
Is the problem reproducible on two different computers? If the problem stays with the mouse you may need to dis-assemble it and clean it. You may need a can of air and a small screwdriver. If you see no screws on the bottom of the mouse, you may need to lift off the small pads that have an adhesive to them. Underneath the pads there may be accessible screws to remove. Once clean the problem may go away. If the problem remains, you may need a new mouse.