I just lost three hours of my life by giving in to the constant splash screens telling me to upgrade to win. 10....At first it was installing as expected, but when it rebooted and gave me the sign on screen it was frozen with a little circle spinning.... If I clicked around long enough the page would fade and give me a black screen. Tried to boot into safe mode but didn't work. Reboots resulted in the same outcome. I had a perfectly functioning system and then I had a mess. I unplugged my USB wireless gadget and then it did boot up....I flew to the security screen and rolled back to seven.....thank god. Moral of the story is.....do your homework before installing. If I'd seen all the problems people are having I wouldn't have done it.