Windows 10 BSOD after using Update Troubleshooter

After the nth failed update to my Windows 10 Professional installation - forcing me to restart my laptop twice for the attempt to install and the rollback - I got fed up with it, and decided to look into a complete reset of the updates. After all, I have hidden lots of updates after failed attempts, and this will logically result in entropy (which Windows has enough of as it is).

So I ran the Windows Update Troubleshooter, 'fixed' a found error, and now starting my laptop, even in Safe Mode, results in a Blue Screen of Death, with error code ' 0xc000021a'.

According to the help center my laptop boots into after a failed start, I don't have any System Restore Points, and the only other viable options seem to be
1). a complete reinstallation, which will let me lose all installed programs, and
2). use third-party software to target the (presumably) corrupted files, but I have no idea what software would be appropriate.

Does anyone know a method to get past this problem without forcing me to go through a complete reinstall of all software?
Or, more specifically and specialistically, does anyone know how to fix the files the Troubleshooter in all probability has changed?
Can anyone suggest the appropriate software for a USB recovery tool?