Try disconnecting from the internet before starting the Upgrade over.
Look over this tutorial for a gold standard Clean Install which compiles the best possible Install of Windows which will stay that way as long as you stick with the tools and methods given, has zero reported problems, and is better than any amount of money could buy: http://answers.microsoft.com/en-us/windows/wiki...
Note that the driver steps are so important they are printed in red.
The reason I suggest this install is that no one of millions who has done it has ever come back to report further problems I've seen, including another version failure. This is because everything in Windows 10 is dependent upon the quality of the install, especially Version Updates which will choke on lesser quality installs, and there is no possibility of problems if you stick ONLY with the steps, tools and methods in that tutorial.
It is also one of life's great learning experiences that will permanently make you the master of your PC because you will learn everything that works best and how to keep it that way.