Hi Barry, I have an Asus X550C and encountered the same issue, I was going through all the suggestions on this thread but none of them worked (including the 3 shut downs and choose reset). However I did eventually stumble across a fix. Select your Language when prompted then go to Troubleshoot. Now I've forgotten the precise steps so please forgive me but one of the options give you the option of which Windows to boot from, you have the option of Windows Rollback then one or 2 Windows 10 volumes, there is somewhere an option to choose the default volume, in here choose one of the Windows 10 volumes and not the rollback one and restart and this should boot to the original Windows.
Hope that helps everyone!
Cheers
Adam