I recently needed to replace my mouse and Walmart didn't have the rollerball type - only a laser one. It didn't come with any installation anything, but since we plugged it in, the computer has been a little whacky. I've had to Restore several times and my daughter can't get on to her Myspace. Could it be the mouse? Just a coincidence? At one point it was saying "static" in a little window and nothing was working so I did a trick a phone help person had me do once... turn off the computer and unplug everything but the power cord and hold the power button down for a full minute. That worked like magic, but only for half an hour. Any advice or clues? I have medium/low computer ability. It said on the mouse packaging to make sure your computer had the capabilities, but the rest was too gobblety gook for me to understand.