As per last comment, removing systemd-shim solves this. "Me too" subscribers, please review whether this solves the problem for you also. It's fairly likely that your problem is actually different; look for other bugs with similar symptoms.
** Changed in: systemd (Ubuntu) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1730272 Title: package systemd-sysv 234-2ubuntu12.1 failed to install/upgrade: subprocess installed post-removal script returned error exit status 2 Status in systemd package in Ubuntu: Invalid Bug description: systemd-shim also failed to install ProblemType: Package DistroRelease: Ubuntu 17.10 Package: systemd-sysv 234-2ubuntu12.1 ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4 Uname: Linux 4.13.0-16-generic x86_64 NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia ApportVersion: 2.20.7-0ubuntu3.1 Architecture: amd64 Date: Mon Nov 6 10:19:01 2017 ErrorMessage: subprocess installed post-removal script returned error exit status 2 InstallationDate: Installed on 2014-02-21 (1354 days ago) InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1) Python3Details: /usr/bin/python3.6, Python 3.6.3, python3-minimal, 3.6.3-0ubuntu2 PythonDetails: /usr/bin/python2.7, Python 2.7.14, python-minimal, 2.7.14-2ubuntu1 RelatedPackageVersions: dpkg 1.18.24ubuntu1 apt 1.5 SourcePackage: systemd Title: package systemd-sysv 234-2ubuntu12.1 failed to install/upgrade: subprocess installed post-removal script returned error exit status 2 UpgradeStatus: Upgraded to artful on 2017-11-05 (0 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1730272/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp