[. . . ] Getting started with Première utilisation Logitech® Wireless Trackball M570 Getting started with Première utilisation Logitech® Wireless Trackball M570 Insert the Unifying receiver into a computer USB port near your M570. [. . . ] Mac® users will also need the software to enable the back, forward, and middle button functions. Now add a compatible wireless keyboard that uses the same receiver as your mouse. If the Unifying receiver is plugged into a USB hub, try plugging it directly into your computer. Move the Unifying receiver to a USB port closer to the trackball, or go to www. Com/usbextender for a USB extension stand that will allow the Unifying receiver to be placed closer to the trackball. Logitech, the Logitech logo, and other Logitech marks are owned by Logitech and may be registered. [. . . ] Logitech assumes no responsibility for any errors that may appear in this manual. [. . . ]