I'm new to Linux and trying to install Linux Mint on a Windows 11 laptop. I downloaded Mint and used balenaEtcher to create a bootable USB drive. The first time I booted from it, Mint started normally and I was able to test it. During installation, I chose the option to keep Windows, but that wasn't possible because BitLocker was enabled. I then disabled BitLocker encryption and restarted the computer.
Since then, the USB no longer boots Mint. Depending on how I restart the laptop, Windows starts normally or I receive this error when selecting the USB:
"Failed to open \EFI\BOOT\mMx64.efi - Not FoundnFailed to load image: Not FoundnFailed to start MokManager: Not FoundnSomething has gone seriously wrong: import_mok_state() failed: Not Found"
Why did the USB work before, and could disabling BitLocker have caused this? What should I try to get the Mint installer booting again?
2 Answers
The restart option in Windows is just a way to reach the firmware or boot-device menu. You can also shut the laptop down completely, connect the USB, power it on, and repeatedly press the manufacturer’s boot-menu key—often F12, Esc, F9, or F10. Select the entry that names the USB drive. If it still produces the missing EFI-file error, recreate the installer rather than attempting the installation again from that copy.
BitLocker probably isn’t the cause of this particular error. The message means the UEFI firmware is trying to boot from the USB but can’t find one of the EFI files it expects. The ISO or the USB creation may have become corrupted, or the drive may not have been written correctly.
Download the Mint ISO again from the official source and verify its checksum if possible. Then recreate the USB, preferably with a different flash drive if you have one. Rufus in DD mode is another option besides Etcher. Afterward, use the laptop’s one-time boot menu or UEFI settings and explicitly select the USB device—not the Windows boot entry. Also make sure the USB is plugged in before powering on.
I changed the boot order in the firmware settings, but the same error remained. That points even more strongly to the installer USB or ISO, so I’ll recreate it rather than keep changing Windows settings.