could not load the secure boot enrollment menu

[Tom Elliott]

@robertkwild The issue most likely is not coming from the flip of Secureboot On/Off.

Unsigned or test-signed boot drivers. This is where a real BSOD can happen. If the machine has bcdedit /set testsigning on or nointegritychecks, and a boot-start driver depends on that (an unsigned storage or RAID driver, some sketchy anti-cheat, a dev build), turning Secure Boot on makes those settings get ignored. If the storage driver doesn’t load, you get INACCESSIBLE_BOOT_DEVICE. That one only happens in the off-to-on direction.