I assume that System Restore in the recovery environment shows that no restore points are available?
No, none. And after spending hours on remote chat/phone with Microsoft tech support they've pretty much screwed up any chance of using them.
Yesterday I did manage to start up Windows 10 - it's still shaky and I'm downloading and installing drivers and updates with some success, but after spending an entire week going over dozens of videos, posts, comments etc I'd like to share what DID work for me and how I managed.
After most of what I tried didn't work (in-place repair installation, system restore, startup repair, etc.) and I couldn't even start Windows 10 in safe mode (stuck with spinning dots and black screen indefinitely), I tried to boot with Kyhi's Windows 10 Recovery Tools (Windows PE boot worked) and then with Hiren's BootCD (amazing and must-have!). I tried running various commands including bcdedit, bootrec, diskpart, dism variations - nothing worked. Safeboot with bcdedit didn't work, bootrec kept giving me those "access denied" errors with fixboot, dism gave various errors as well. Microsoft's tech support insisted that I try to copy the system hive files (SAM, DEFAULT, SYSTEM, SOFTWARE, SECURITY) from the RegBack folder. I noticed that they were all "zero" size but tech support insisted I copy them and overwrite the existing files in the config folder. Unfortunately, Microsoft stopped backing up up those files automatically from build 1803 (which I have now) so it was a really dumb thing to advise me to do. "Kudos" Microsoft tech support. Luckily I backed up the files before I ran them over. But still there was no progress.
So I gave up and just wanted to backup using Acronis as much as I can and then reinstall Windows - but I needed to purchase a key as it's not free. Bummer. But the recovery option is still free. I found an old full backup I made using Acronis back in January 2019 and decided to try one last thing - to copy the system hive files from the old backup and plant them in the c:\windows\system32\config folder. I copied the 5 system hive files and rebooted, which produced error 0xc000014c with File: \Windows\system32\config\system. So I renamed the config folder to config.old and copied the entire folder from the backup to my computer. Tried to restart and got an error 0xc00000f with File: \Windows\System32\DRIVERS\Klelam.sys. I couldn't find any relevant solutions anywhere (most suggestions were "do a clean install") so I went to my old backup and copied the entire c:\windows\system32\drivers to my computer. Along the way I also copied the c:\boot folder as well. Tried to boot and - OMG! -
Windows 10 booted into safe mode minimal. I wanted to try and boot to normal mode but got stuck in a safe mode boot loop, even though I unchecked the safe boot option in msconfig. I tried various bcdedit /deletevalue {default} safeboot options but all produced errors. So I tried using "bcdedit /set {default} safeboot network" followed by "bcdedit /deletevalue {default} safeboot" and restarted. Windows 10 loaded in all its (shaky) glory! I installed some updated drivers (display, chipset, etc) to make it functional again - and now I'm running some more driver and updates installations.
I expect I'll have to do a clean install anyway as it's currently a bit of a Franken-Windows setup with old/new/corrupted files - but at least I can back it up properly now and still get some work done - which was cut short a week ago with the numerous issues I've had. Boot time's even better at under 1 minute - which was what I wanted in the first place :)
That's my 2 cents, hope someone would benefit from my experience. I'm not a that tech savvy but I don't fear diving into the nuts and bolts of the Windows installation, and my stubbornness and tenacity are what drove me to pull this off.
