Installed Windows 10 Fall Craters update, which ran without issues. Ran Windows repair and attempted to reboot. Now the machine reboots to a permanent black screen, and I'm in big trouble.
I see the HP splash screen, the blue Windows 10 logo with a spinning circle, a black screen with a spinning circle, and then black screen forever. I never see the login screen.
The recovery console reports there are no registry restore points, although I always make a backup in Windows Repair. It just can't find them for some reason.
I allowed Windows Recovery to run, and it says it can't repair the startup process.
I've forced it to attempt to start up in Safe Mode. Same result.
I can get to a C: prompt using the recovery console. Chkdsk shows no problems. sfc /scannow ran to completion, but said it could not perform requested actions. Unsure of what that meant.
The machine has a RAID 1 (mirrored) array with two drives. It reports there is a critical error on drive 0, suggesting a partition error of some sort (no issues reported prior to this). Removing this drive and attempting to boot from drive 1, which is reported as healthy, produces the same black screen result.
This machine is about to be retired, but it has thousands of files I need to transfer to the new machine. It's a long time favorite client I don't want to lose.
How do I recover from this?