I downloaded the repair iso from the link you gave me. I configured the BIOS to boot from CD/DVD. I have opened a boot device menu and chosen to boot from CD/DVD, and got the media media test failure message.
When I try to start my toshiba satellite L455D-S5976, it gives me the option between "start normally" or "system repair." When I chose "start normally," it shows the windows boot screen for a while, then restarts to the toshiba start screen, and the same menu again. If I chose "system repair,"...