If you encounter any of the following errors, follow this simple tutorial to get your Slimbook working again:

Could not create MokListRT: Volume Full
Could not create MokListXRT: Volume Full
Could not create SbatLevelRT: Volume Full
Could not create MokListTrustedRT: Volume Full
Something has gone seriously wrong: import_mok_state() failed: Volume Full

First, it is important to understand why this happens.

Machine Owner Keys (MOKs) are cryptographic keys associated with Shim, a program used by most Linux distributions for Secure Boot. Secure Boot requires that bootloaders be signed with a key to verify their authenticity. Although some public keys are stored in the computer's firmware or NVRAM, a common problem occurs when the EFI Boot Entries become full, which can happen if the operating system updates GRUB after an update.

To clear the EFI boot entries and fix this issue, you need to reset the BIOS settings to factory defaults. This will erase the EFI Boot Entries and allow you to boot your operating system again.

To fix this, follow these steps:

 1. Access your Slimbook's BIOS (by pressing F2 or DEL, depending on the model).

 2. In the "Save & Exit" or "Exit" window, look for the "Default Options".

 3. Select "Restore Defaults" or "Load Optimized Defaults".

 4. Confirm with YES and then save the settings with F4 or "Save & Exit".

 5. When computer restarts, access your BIOS once more to ensure that Secure Boot and Quiet Boot are "Disabled", and then again save settings with F4 or "Save & Exit".

 With this, the EFI entries will be reset and the system should boot without problems.

If it still doesn't work or you get another error, do not hesitate to open a ticket at https://slimbook.com/support