Example of some error output:
dpkg: error processing package grub2-common ... grub-pc depends on grub-common (= 2.04-1ubuntu26.13); however: Package grub-common is not configured yet. ... No apport report written because MaxReports is reached already No apport report written because MaxReports is reached already
Run this:
sudo apt-get purge grub\* sudo apt-get install grub-efi sudo apt-get autoremove sudo update-grub
Go to rescue console/boot livecd depending on your environment.
If the server has raid 1 setup follow Reinstall grub on mdraid1 array