Can't boot with "Error: No such device: c3b9817..."

[Aravisian]

[HOW TO] enter Recovery Grub Menu (Advanced Options for Zorin)

To enter the Recovery Menu on Zorin OS if using Legacy (MBR) boot, you can hold or tap the Left Shift key at boot to be offered the Advanced Options for Zorin Grub menu. If using EFI Boot, then tap the esc key vigorously. Some users report that the tab key worked, instead. You might think that this is pretty straight-forward. However... Some BIOS are programmed to ignore a key being held down, as it is assumed to be pressed by accident or a stuck key. Cat on keyboard, coffee... The BIOS prog…