I have an acer desktop that came with windows 8.1 that I upgraded to windows 10, I want to restore windows 8.1 but windows 10 won't let me use my USB recovery I made when I still had windows 8.1, I boot from the drive, but all's I get is a language and keyboard layout questions. Then my options become Continue (Exit and Continue to Windows 10), Use a device, Troubleshoot, and Turn off your PC. I got to advance settings to select USB but all's that does is cause a 2 sec pause than a reboot. I really want 8.1 as it gave a smoother experience than 10.