[O/S] debian has been blocked by current security policy

[mahdi]

Hi. I'm kinda a beginner to linux and Debian and ran into a problem.

TLDR;
After re-installing Grub and doing a reboot, I got an error on booting Debian:

cannot find TOCBLOCK database may be corrupt

I fixed this issue with Boot-Repair, but now I can't boot it with Secure Boot enabled (it was fine before Grub re-installation), getting a blue screen with message "debian has been blocked by current security policy." I'm running a dual-boot setup with Debian and Windows. How can I fix this with SB enabled?

Detailed question:
I wanted to add Windows 10 to the Grub boot menu. I found this web page and followed the instructions. The "update-grub" command couldn't be found by my system so I visited this question, and thought this answer would be easy to do. After running the command I got a message on screen which told me to reboot the system. After rebooting, I couldn't boot Debian and got "cannot find TOCBLOCK database may be corrupt" error on a black screen.

Then I googled the error and ended up with Boot-Repair. So I booted Debian Live on a USB stick and installed Boot-Repair. Then I did the repair with one extra non-default option: "Place the boot flag on" and set it to the Debian partition on my disk. The Grub was removed and re-installed from the partition and gave me this output log.

Now I can boot Debian, but only when I disable Secure Boot. If it's enabled I get this error on a blue screen with an OK button:

debian has been blocked by current security policy

When I press OK, the second OS shows up. This happened recently after I re-installed Grub. I want SB to be enabled, as it was before. How can I fix this?
Here's my kernel log, output of "dmesg" command: https://pastebin.com/WJ3AGexU

[pbear]

If you're new to Linux, who has been playing mad scientist with your computer? Has had a couple of operating systems, still has a couple of EFI partitions, and the partitions seem to have been moved around a lot. Also, what's with the dynamic disks in Windows? Linux can only handle those with a kludge called ldmtool. Frankly, the best solution would be to get rid of the dynamic disks, by reinstall of Windows if necessary, then reinstall Debian.