Hello, I installed Windows 8 on a friends laptop and now he wants to go back to Windows 7. I already downloaded an ISO file from a site called Dreamsparks which allows students at my school to get software for a huge discount or free. I then went ahead and used Windows7 USB download tool to get the ISO onto my USB. When I tried to boot up the laptop from the USB I got a blue screen with this error: "A problem has been detected and windows has been shut down to prevent damage to your computer. .... Check with your hardware vendor for any BIOS updates. Disable BIOS memory options such as cashing or shadowing. If you need to use Safe Mode to remove or disable components, restart your computer, press F8 and Select Advanced Startup options, and then select Safe Mode. " Anyone know what might be wrong?