"The computer restarted unexpectedly..." error after boot problems

After updating to Windows 1903 my computer was showing the message "Reboot and select proper boot device". After following the fix listed here I ran into a new problem.
The first time I booted up my SSD after applying those fixes, I was met with "Windows is updating" screen and its progress was around 48%. After about a minute it restarted itself. Upon booting up I got a message that said "The computer restarted unexpectedly or encountered an unexpected error. Windows installation cannot proceed. To install Windows, click “OK” to restart the computer, and then restart the installation."

Most of the fixes for this problem suggest using shift+F10 and opening command prompt and going to regedit. But I can't access command prompt no matter what I do. Shift+F10 does not open anything. Pressing OK on the prompt simply restarts the computer and brings me back to the same message. Is there any fix for this besides reinstalling? Thanks in advance.

Please find a camera or smart phone camera to take pictures and post images into the thread.

When the computer is powered on now what do you see and hear?

On a working computer create a bootable windows 10 iso:
https://www.microsoft.com/en-us/soft...load/windows10

Boot to the Windows 10 iso and open the Windows advanced troubleshooting menu.

Indicate whether you want to:
a) continue troubleshooting (some steps may be repetitive to view results in the thread)
b) perform a reset save files equivalent (reinstall drivers and applications)
c) clean install

Unfortunately, I already reinstalled Windows. I did troubleshooting with a Windows 10 ISO but couldn't really get anywhere. Thanks anyway.

Access denied is a very challenging boot failure.
Most often with recent versions of Windows 10 most troubleshooting steps fail.

Glad to see that you backup and running.

For older Windows builds regback was a troubleshooting option.
Recent windows versions do not have the automatic regback.

Microsoft has a feedback hub.
Please send your feedback so that automatic regback can again be an option as a working troubleshooting step.
It is only manual now and end users would have had to plan ahead for the unexpected failure.

Another boot failure option is a reset save files equivalent using the iso but this requires re-installations of drivers and applications.

There is free cloud storage for limited space.
Consider obtaining a storage drive and saving a free backup image for unexpected malware, ransomware, operating system an or registry corruption, failure to boot, drive failure, etc.

Again please send feedback to Microsoft:
https://support.microsoft.com/en-us/...edback-hub-app