Has Win10 1903 upgrade destroyed my system partition?

Question

tl;dr. Yes, Windows 1903 update destroyed my system partition. Thanks, Microsoft.

After failed 1903 upgrade (from current Win10 1803 installation), my computer won't boot, says Boot Manager Missing. All standard solutions fail (I won't bother listing them at this point). I have a vhdx system image on a second drive but only get failure when attempting to restore. In WinRE command prompt, chkdsk reports no problems, bootrec.exe /scanos reports it can't find an operating system, bootrec /fixmbr says access denied, and diskpart list vol says that my system partition has format RAW. This seems bad, but maybe there's still a way to recover? Or is my system partition totally unrecoverable (such that I just need to do a bare metal windows install and then hope that my system image will restore on it?

In this output of diskpart list vol you can see Vol 2 (111GB) which is my system partition (on an SSD, if that matters), Vol 3 is a second data-only hard drive, Vol 4 is the USB stick that I used to boot WinRE.

Answer 1

That doesn't look good!

Right now, I'd say that bootrec.exe /scanos fails because, according to this:

/ScanOs This option scans all disks for installations that are compatible with Windows Vista or Windows 7. It also displays the entries that are currently not in the BCD store. Use this option when there are Windows Vista or Windows 7 installations that the Boot Manager menu does not list.

(I know this documentation says Windows 7 or Vista, but this shows that bootrec is part of Windows 10, so I'm not too worried about the differences.)

Since your installation partition is now showing up as RAW, I would say that bootrec doesn't work because the partition isn't in a format that bootrec can read.

My first step would be to backup the whole drive, bit for bit, using a linux live cd (like Ubuntu, but anything would work, really) and the utility dd. Be REALLY careful using dd, as you can just as easily erase everything on the drive as you can make a backup.

(Another option would be a tool like Clonezilla, in case you don't want to risk it with dd.)

Then, with a backup in place, I would try to use a utility to recover the NTFS partition. TestDisk is one that I would probably try, but I'm sure there are many options.

After that, I would try bootrec.exe /scanos again see if the normal Microsoft tools can got you back up and running.