I got mine fixed with the following:

Firstly removed gdm:

sudo apt purge gdm gdm3 etc


Then installed:
sudo apt-get install --reinstall ubuntu-desktop
sudo reboot

On Mon, Oct 22, 2018 at 8:52 AM Alejandro <email address hidden>
wrote:

> Histill having the same problem  with the "systemd-shim"I don't know how
> to fix it May be I will format everything and reinstall Ubuntu 18
> againgreetings
>
>       From: José Enrique <email address hidden>
>  To: <email address hidden>
>  Sent: Thursday, October 18, 2018 3:10 AM
>  Subject: Re: [Bug 1773859] Re: upgrades to 18.04 fail
>
> Hy, in this moment I can't update my laptop or install any package or
> program
> Greetings
>
> El mié., 17 oct. 2018 23:11, Brian Murray <email address hidden> escribió:
>
> > ** Tags added: bugpattern-written
> >
> > --
> > You received this bug notification because you are subscribed to a
> > duplicate bug report (1792241).
> > https://bugs.launchpad.net/bugs/1773859
> >
> > Title:
> >  upgrades to 18.04 fail
> >
> > Status in systemd package in Ubuntu:
> >  Fix Released
> > Status in systemd-shim package in Ubuntu:
> >  Won't Fix
> > Status in systemd source package in Bionic:
> >  In Progress
> > Status in systemd-shim source package in Bionic:
> >  Won't Fix
> > Status in systemd source package in Cosmic:
> >  Fix Released
> > Status in systemd-shim source package in Cosmic:
> >  Won't Fix
> >
> > Bug description:
> >  [Impact]
> >
> >    * Some systems fail to upgrade due to conflicts between systemd and
> >  the (now removed from the archive) systemd-shim / upstart.
> >
> >    * Instead of trying to work out what's the problem in ordering /
> >  removal of diverts, ensure that systemd is never unpacked whilst
> >  systemd-shim/upstart are still on disk. Thus declare conflicts against
> >  systemd-shim/upstart packages in systemd package.
> >
> >  [Test Case]
> >
> >    * monitor drop-off of upgrades with below reported problem
> >
> >    * Check that it is possible to upgrade to bionic's libpam-systemd
> >  from xenial with systemd-shim installed on xenial.
> >
> >  [Regression Potential]
> >
> >    * systemd-shim/upstart are both removed and not supported in bionic,
> >  thus forcing their removal via conflicts should bring the system into
> >  an expected state.
> >
> >  [Other Info]
> >
> >    * original bug report
> >
> >
> >  $ sudo apt upgrade
> >  Reading package lists... Done
> >  Building dependency tree
> >  Reading state information... Done
> >  Calculating upgrade... Done
> >  The following packages will be REMOVED:
> >    systemd-shim
> >  0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
> >  1 not fully installed or removed.
> >  After this operation, 71.7 kB disk space will be freed.
> >  Do you want to continue? [Y/n] y
> >  (Reading database ... 632222 files and directories currently installed.)
> >  Removing systemd-shim (9-1bzr4ubuntu1) ...
> >  Removing 'diversion of
> > /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service to
> >
> /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.systemd
> > by systemd-shim'
> >  dpkg-divert: error: rename involves overwriting
> > '/usr/share/dbus-1/system-services/org.freedesktop.systemd1.service' with
> >    different file
> >
> '/usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.systemd',
> > not allowed
> >  dpkg: error processing package systemd-shim (--remove):
> >    subprocess installed post-removal script returned error exit status 2
> >  Errors were encountered while processing:
> >    systemd-shim
> >  E: Sub-process /usr/bin/dpkg returned an error code (1)
> >
> >  Commenting out the dpkg-divert in systemd-shim's postrm solved this
> >  for me and I was about to continue the upgrade.
> >
> > To manage notifications about this bug go to:
> >
> >
> https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1773859/+subscriptions
> >
>
> --
> You received this bug notification because you are subscribed to a
> duplicate bug report (1796221).
> https://bugs.launchpad.net/bugs/1773859
>
> Title:
>   upgrades to 18.04 fail
>
> Status in systemd package in Ubuntu:
>   Fix Released
> Status in systemd-shim package in Ubuntu:
>   Won't Fix
> Status in systemd source package in Bionic:
>   In Progress
> Status in systemd-shim source package in Bionic:
>   Won't Fix
> Status in systemd source package in Cosmic:
>   Fix Released
> Status in systemd-shim source package in Cosmic:
>   Won't Fix
>
> Bug description:
>   [Impact]
>
>   * Some systems fail to upgrade due to conflicts between systemd and
>   the (now removed from the archive) systemd-shim / upstart.
>
>   * Instead of trying to work out what's the problem in ordering /
>   removal of diverts, ensure that systemd is never unpacked whilst
>   systemd-shim/upstart are still on disk. Thus declare conflicts against
>   systemd-shim/upstart packages in systemd package.
>
>   [Test Case]
>
>   * monitor drop-off of upgrades with below reported problem
>
>   * Check that it is possible to upgrade to bionic's libpam-systemd
>   from xenial with systemd-shim installed on xenial.
>
>   [Regression Potential]
>
>   * systemd-shim/upstart are both removed and not supported in bionic,
>   thus forcing their removal via conflicts should bring the system into
>   an expected state.
>
>   [Other Info]
>
>   * original bug report
>
>
>   $ sudo apt upgrade
>   Reading package lists... Done
>   Building dependency tree
>   Reading state information... Done
>   Calculating upgrade... Done
>   The following packages will be REMOVED:
>     systemd-shim
>   0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
>   1 not fully installed or removed.
>   After this operation, 71.7 kB disk space will be freed.
>   Do you want to continue? [Y/n] y
>   (Reading database ... 632222 files and directories currently installed.)
>   Removing systemd-shim (9-1bzr4ubuntu1) ...
>   Removing 'diversion of
> /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service to
> /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.systemd
> by systemd-shim'
>   dpkg-divert: error: rename involves overwriting
> '/usr/share/dbus-1/system-services/org.freedesktop.systemd1.service' with
>     different file
> '/usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.systemd',
> not allowed
>   dpkg: error processing package systemd-shim (--remove):
>    subprocess installed post-removal script returned error exit status 2
>   Errors were encountered while processing:
>    systemd-shim
>   E: Sub-process /usr/bin/dpkg returned an error code (1)
>
>   Commenting out the dpkg-divert in systemd-shim's postrm solved this
>   for me and I was about to continue the upgrade.
>
> To manage notifications about this bug go to:
>
> https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1773859/+subscriptions
>
> --
> You received this bug notification because you are subscribed to a
> duplicate bug report (1793916).
> https://bugs.launchpad.net/bugs/1773859
>
> Title:
>   upgrades to 18.04 fail
>
> Status in systemd package in Ubuntu:
>   Fix Released
> Status in systemd-shim package in Ubuntu:
>   Won't Fix
> Status in systemd source package in Bionic:
>   In Progress
> Status in systemd-shim source package in Bionic:
>   Won't Fix
> Status in systemd source package in Cosmic:
>   Fix Released
> Status in systemd-shim source package in Cosmic:
>   Won't Fix
>
> Bug description:
>   [Impact]
>
>    * Some systems fail to upgrade due to conflicts between systemd and
>   the (now removed from the archive) systemd-shim / upstart.
>
>    * Instead of trying to work out what's the problem in ordering /
>   removal of diverts, ensure that systemd is never unpacked whilst
>   systemd-shim/upstart are still on disk. Thus declare conflicts against
>   systemd-shim/upstart packages in systemd package.
>
>   [Test Case]
>
>    * monitor drop-off of upgrades with below reported problem
>
>    * Check that it is possible to upgrade to bionic's libpam-systemd
>   from xenial with systemd-shim installed on xenial.
>
>   [Regression Potential]
>
>    * systemd-shim/upstart are both removed and not supported in bionic,
>   thus forcing their removal via conflicts should bring the system into
>   an expected state.
>
>   [Other Info]
>
>    * original bug report
>
>
>   $ sudo apt upgrade
>   Reading package lists... Done
>   Building dependency tree
>   Reading state information... Done
>   Calculating upgrade... Done
>   The following packages will be REMOVED:
>     systemd-shim
>   0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
>   1 not fully installed or removed.
>   After this operation, 71.7 kB disk space will be freed.
>   Do you want to continue? [Y/n] y
>   (Reading database ... 632222 files and directories currently installed.)
>   Removing systemd-shim (9-1bzr4ubuntu1) ...
>   Removing 'diversion of
> /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service to
> /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.systemd
> by systemd-shim'
>   dpkg-divert: error: rename involves overwriting
> '/usr/share/dbus-1/system-services/org.freedesktop.systemd1.service' with
>     different file
> '/usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.systemd',
> not allowed
>   dpkg: error processing package systemd-shim (--remove):
>    subprocess installed post-removal script returned error exit status 2
>   Errors were encountered while processing:
>    systemd-shim
>   E: Sub-process /usr/bin/dpkg returned an error code (1)
>
>   Commenting out the dpkg-divert in systemd-shim's postrm solved this
>   for me and I was about to continue the upgrade.
>
> To manage notifications about this bug go to:
>
> https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1773859/+subscriptions
>