Hello, I have a dual-boot PC where Windows 7 is on one hard-drive and CentOS 6.7 is on another. Today I stupidly decided to update Windows 7 to Windows 10, but had nothing but BSOD. I then used Windows 10 to go back to Windows 7, but instead I again have BSOD. Anyone know how I can make a boot USB key so that I can re-install Windows 7 and then repair GRUB? Thank you, Brian Bernard