Comment 289 for bug 1289977

@Teo1978, you are using an EFI booting machine, so don't have grub-pc and the dpkg-reconfigure does not apply to you. IIRC, the problem on EFI is that if you have used grub-repair or whatever it was called, it makes a copy grubx64.efi and configures the firmware to boot that instead of the original, then when grub is upgraded, the copy is now stale. You can see which file your system is set to boot with sudo efibootmgr -v, and iirc, the copy was named /boot/efi/EFI/BOOT/Bootx64.efi, and the original is /boot/efi/EFI/Ubuntu/grubx64.efi.