I have the 64bit iso successfully installed on a USB using USB universal. I'm trying to run it on a Toshiba Satellite C55-A. The processor is an Intel i3-3120M and the system type is a 64 bit OS and I'm running windows 8.1. When I boot the USB, the screen goes black and after a few seconds in the upper left of the screen it says Media(fail), then Media(fail) again, then starts booting windows. Any idea what Im doing wrong