hi i have a seagate 500gb portable hard drive that holds all my music and now when i plug it in i cant use it the lights come on and are steady you can hear the drive turning and then the lights suddenly start a constant flashing i go into computer and the seagate goflex hard drive is not even redgistered on there i have tried on another pc and the same happens i have tried numerous usb connecters including buying a new usb3 wire but no luck i just want to recover my files and pictures if i can. would be grateful if anybody can help ?