I just installed the MS trackball optical and I can't get the back-forward buttons to work. They only work if I'm in the USER'S GUIDE or in Explorer. I went to the web page and I downloaded the newer version of Intellipoint(version4) and I also downloaded their user guides. When I tried to access them the computer said "file hh.exe could not be found." I am a novice-please go easy on me-I need details. I have an eMachines computer and Windows ME.