"how can I reinstall windows 10 from usb when pc won't boot up, tried to do it from boot menu, set boot to usb, push enter. screen goes to a window and dots spinning in a circle,does that for 4 or 5 days with no changes. how long should it have to run? Iremember resetting xp you were good to go in 2 or 3 hours but not days. what can I do?"