After installing the Windows 10 "Creators" update, I pressed the "Project" key to display on my external monitor. The popup screen said "Your PC can't project to another screen. Try reinstalling the driver or using another video card." I can't find a solution to this problem so, since Windows 10 keeps updating automatically, I just want to go back to Windows 7. Of course, it's been much longer than a month since I installed Windows 10, so I have to do a clean install of Windows 7. Belarc gives me a key for my Windows 10. Will this key work for doing a clean install of Windows 7?