My Lenovo laptop came with Windows 8, and shortly after getting it, I upgraded to Windows 8.1, totally unaware of the fact that Microsoft fails and I lost my ability to "Remove everything and reinstall Windows." I found a workaround by using the free Windows 8.1 Enterprise Evaluation, however, because it's expired, my laptop shuts down every hour. How can I get my Windows 8 back? Like I said, I already owned it before, but my Laptop CAME with it, so I don't have a media disc, also the Lenovo Y510P does NOT have a disc tray, so I can't get a new copy. If I reset my laptop to factory settings, will that reset with Windows 8 or Windows 8.1 Enterprise Evaluation?