I have created an USB key with Mint, but when I boot from it I get a few lines of errors
- Failed to open \EFI\BOOT\mmx64.efi - Not Found
- Failed to load image ??: Not Found
- Failed to start MokManager: Not Found
- Something has gone seriously wrong: import_mok_state () failed: Not Found
I have tried disabling safe boot, and fast boot. I have confirmed that my system has UEFI.
I believe that I once managed to run Mint off the USB but have not managed to do so since
This just happened to me, once you make the bootable USB, open it up, go into EFI/boot, and copy grubx64.efi, then rename it to mmx64.efi
Everything should work from there.
mmx64 is the MOK manager. It’s a tool used to set up secure boot correctly so you can use secure boot with Linux. It’s supposed to run at least once for secure boot setup to get the basic keys loaded into the system.
Putting grub in its place will boot Grub directly, but you just end up with a misconfigured boot setup that’ll only break when Grub eventually updates, or lacks Grub security updates since you copied rather than linked the bootloader.
Your suggestion fixes the symptoms, but not the problem. The real solution will involve either installing the necessary tooling (like MOK Manager) correctly, or altering the UEFI boot configuration to load Grub rather than the MOK manager.
The latter option may require secure boot to be disabled, though.