Clip+ No Longer Recognized by any Computer

If it’s any use: I’ve noticed that my Clip+ is never recognized on a Dell laptop WIn 8.1 that has USB 3 ports only.  On my other WIn 7 PC with both USB and 2 ports,it is only recognized on a USB 2 port. If your PC has USB 3 ports, try plugging your player on a friend’s PC with USB 2 ports.