I just tried to update Windows 10, on the first boot windows crashed. When I restarted I got the message no operating system found. Luckley (I thought) I created a recovery USB drive before updating. First I booted from that drive and tried to repair start-up--didn't work. I then tried to restore a system image from an attached USB hard drive--didn't work(tried 3 times). It found the image but quit after loading about 65% then aborted. My final attempt was to use the recovery option which I knew would delete all my files..also didn't work.

Any ideas?