Hello, I just upgraded to a new g5 iMac 20", 10.3.7, and moved all my files and settings over to it. When I plugged in my wireless MS Intellimouse Explorer it was immediately recognized and worked ...partially. The left, right and scroll worked fine, but the back and forwards buttons did nothing. I uninstalled the old software, downloaded and installed latest (Intellimouse 5.1), but still no recognition of the buttons. The Intellimouse control panel shows a big red X through the illustration of another model of mouse. There are no menus for the back and forward buttons. I've now made multiple attempts at this without success. MS website doesn't recognize the product ID number it asked for to provide me with email support, so I can't get help from them. Any help will be appreciated. Thanks, Dave