StartOS installer fails with mmx64.efi / import_mok_state() after replacing NVMe SSD

[George]

Fixing BIOS loop after StartOS install

While StartOS worked well on an earlier similar Minisforum model (the UN1265), I discovered that the Minisforum UN1290 doesn’t go as expected. This model is running a newer/nicer BIOS (listed on the Main tab as “BIOS Version 1.06”, and in the footer as “Version 02.22.0058 Copyright American Megatrends International LLC”). The installation goes fine, but upon reboot, the miniPC behaves as if there is no bootable device. After some tinkering, I’ve gotten it to work with a minor hack, so thought…