System keeps scanning and repairing after every boot / reboot and frequent BSOD

Download RUFUS and DBAN (use google to find them),

Use Rufus to create bootable USB stick with DBAN iso.

Put the stick in and restarts. It will go into blue screen with DBAN settings - chose to nuke the drive. It will take a long time (maybe even a day, maybe just hour) and it will erase everything from it.

In BIOS you must set USB read first before OS from the disk.

Afterwards reinstall windows 10 from USB. You obviously need another PC for this or two USB sticks, to get Windows 10 installation ISO ready on USB.

It could be that whatever registry you changed damaged or somehow locked the part of the disk. Though I never seen this happen on SSD. Anyway, DBAN should erase everything from there.

/r/Windows10 Thread