Too many causes from USB wireless mice to other. Your post is too slim on details so think back to when it worked.
Bob
My laptop will not time out and go into my screensaver. I have read several answers on help forums and nothing is working. I have an HP notebook with Windows 7 and am currently using Google chrome (if that matters).
Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic