A few days ago, my optical mouse stopped working with my computer. After several trials and errors, I've discovered that my computer only detects mice without a scroll wheel. If there is a scroll wheel, a cursor appears in the middle of the screen as it should, but I can't control it at all. It just sits there. I don't know how this happened because mice with scroll wheels used to work fine. By the way, I'm running Windows XP, and my mouse plugs into my PS/2 port. Thanks for your help!