package systemd-sysv 237-3ubuntu10.3 failed to install/upgrade: installed systemd-shim package post-removal script subprocess returned error exit status 2

[Riccardo]

The error appeared on reboot after update from 16.04 to 18.04

During the version update something went wrong.
A message about systemd-sysv 237-3ubuntu10.3 appeared, with the additional info that the system could be instable and that the tool will run a "dpkgsomethingelse -a".

I launched the update software and i see a notification that asserts that is not possible to install all updates and invite to run a partial update.

Partial version update -> 1 package is going to be removed -> systemd-shim - shim for systemd
Then:
Could not install 'systemd-shim'
The upgrade will continue but the 'systemd-shim' package may not be in a working state. Please consider submitting a bug report about it.
installed systemd-shim package post-removal script subprocess returned error exit status 2

FIX THAT WORKED FOR ME:
--------------------------
cd /usr/share/dbus-1/system-services/
sudo mv org.freedesktop.systemd1.service org.freedesktop.systemd1.service.bak
Then Run Update -> Run Partial Upgrade

ProblemType: Package
DistroRelease: Ubuntu 18.04
Package: systemd-sysv 237-3ubuntu10.3
ProcVersionSignature: Ubuntu 4.15.0-29.31-generic 4.15.18
Uname: Linux 4.15.0-29-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.2
Architecture: amd64
Date: Thu Aug 2 11:21:11 2018
ErrorMessage: installed systemd-shim package post-removal script subprocess returned error exit status 2
InstallationDate: Installed on 2013-11-09 (1726 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
Python3Details: /usr/bin/python3.6, Python 3.6.5, python3-minimal, 3.6.5-3ubuntu1
PythonDetails: /usr/bin/python2.7, Python 2.7.15rc1, python-minimal, 2.7.15~rc1-1
RelatedPackageVersions:
 dpkg 1.19.0.5ubuntu2
 apt 1.6.3
SourcePackage: systemd
Title: package systemd-sysv 237-3ubuntu10.3 failed to install/upgrade: installed systemd-shim package post-removal script subprocess returned error exit status 2
UpgradeStatus: Upgraded to bionic on 2018-08-02 (0 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.