> Windows 8.1 - Open the marketplace, click the button, download, prepare for installation, reboot, begin installation, verify installation, hang, blue screen,

> Windows 8.1 - Open the marketplace, click the button, download, prepare for installation, reboot, begin installation, verify installation, hang, blue screen, reboot, hang, blue screen, reboot, revert to previous installation, reboot. This has not been my experience, at all, on 4 different machines. It was more: Open the marketplace, click the button, download, ask for reboot, reboot, wait for a bit of time (between 15' and 30' depending on the machine), and boot to the new login upgrade. I had a bit of a headache to understand how not to upgrade to a Microsoft account and keep a local account, but that's it.