Computer does not recognize the mp3 player

You could try a usb info cleaner as this one (for win XP) : http://www.nexcopy.com/downloads/USBScrub.zip or this one for XP/Vista/Seven : http://nirsoft.net/utils/usb_devices_view.html Try to clean all USB entries with Sandisk or Clip, restart PC and try again to plug your Clip