package grub-common 2.02~beta3-4ubuntu7.1 failed to install/upgrade: underprosessen installerte post-installation-skript returnerte feilstatus 1

[Dag Bjerkeli]

Did a first time upgrade of an 17.10.1 installation on a PC with encrypted disk, and I did
sudo apt update
sudo apt upgrade

PC was rebooted after install.

I had problems connecting to internett during install and the instructions to enter EFI I was not able to complete.

Additional information:
$ lsb_release -rd
Description: Ubuntu 17.10
Release: 17.10

ProblemType: Package
DistroRelease: Ubuntu 17.10
Package: grub-common 2.02~beta3-4ubuntu7.1
ProcVersionSignature: Ubuntu 4.13.0-21.24-generic 4.13.13
Uname: Linux 4.13.0-21-generic x86_64
ApportVersion: 2.20.7-0ubuntu3.7
Architecture: amd64
Date: Tue Feb 27 20:53:27 2018
ErrorMessage: underprosessen installerte post-installation-skript returnerte feilstatus 1
InstallationDate: Installed on 2018-02-27 (0 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20180105.1)
ProcCmdLine: BOOT_IMAGE=/vmlinuz-4.13.0-21-generic.efi.signed root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
Python3Details: /usr/bin/python3.6, Python 3.6.3, python3-minimal, 3.6.3-0ubuntu2
PythonDetails: /root/Error: command ['which', 'python'] failed with exit code 1:, Error: [Errno 2] Fila eller mappa finnes ikke: "/root/Error: command ['which', 'python'] failed with exit code 1:": "/root/Error: command ['which', 'python'] failed with exit code 1:", unpackaged
RelatedPackageVersions:
 dpkg 1.18.24ubuntu1
 apt 1.5.1
SourcePackage: grub2
Title: package grub-common 2.02~beta3-4ubuntu7.1 failed to install/upgrade: underprosessen installerte post-installation-skript returnerte feilstatus 1
UpgradeStatus: No upgrade log present (probably fresh install)