For the last 2 years, Microsoft has be download various Windows 10 upgrades, each time the upgrade would hang at 83%. I would power the unit down and re-boot. The previous version would reload and I would continue on. Well, this time it went to 86% and hung. I turn the computer off and the on, the message appears on the screen "loading previous version", then a black screen, and the message appeared again. The unit would not boot. I had purchase the unit at Best Buy, so I went there, The Geek Squad was more than happy to look at it for $109.00. I had no choice. The tech indicated that the upgrade had created multiple partitions and he would have to format and reload the OS. I called Microsoft's Support number and was told they couldn't help me with a credit or reimbursement. How can a company corrupt your computer and not take responsibility.