how do I get software centre to work

https://help.ubuntu.com/community/PackageManagerTroubleshootingProcedure

Please post the full Terminal output from step 6 and step 10 and put the output here:

https://answers.launchpad.net/ubuntu/+question/448574

Alternatively, you could simply install synaptic as an alternative to Ubuntu Software Center using these Terminal commands:

sudo apt-get update

sudo apt-get install synaptic

Your choice :-)

Does apt-get run OK?

Hi Mark, here is the output to Q:6.

ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ ubuntu-support-status
Support status summary of 'ru12mugthe2nd-Satellite-L300':

You have 1766 packages (89.0%) supported until April 2021 (5y)
You have 166 packages (8.4%) supported until April 2019 (3y)
You have 16 packages (0.8%) supported until January 2017 (9m)
You have 23 packages (1.2%) supported until January 2022 (5y)

You have 0 packages (0.0%) that can not/no-longer be downloaded
You have 14 packages (0.7%) that are unsupported

Run with --show-unsupported, --show-supported or --show-all to see more details
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ cat /etc/dpkg/dpkg.cfg.d/multiarch
cat: /etc/dpkg/dpkg.cfg.d/multiarch: No such file or directory
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ dpkg --print-foreign-architectures
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ sudo grep -R proxy /etc/apt/*
[sudo] password for ru12mug-the2nd:
1Sorry, try again.
[sudo] password for ru12mug-the2nd:
Sorry, try again.
[sudo] password for ru12mug-the2nd:
sudo: 3 incorrect password attempts
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ sudo grep -R proxy /etc/apt/*
[sudo] password for ru12mug-the2nd:
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ grep proxy /etc/environment
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$

   Note: At this point terminal refused to accept my password and the whole lot stopped. I closed the terminal and tried again but the terminal would not let me enter my password.
What did I do wrong?

Hi again Mark, here's what I got when I ran your other option.

ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ sudo apt-get update
[sudo] password for ru12mug-the2nd:
Hit:1 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial InRelease
Get:2 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial-updates InRelease [102 kB]
Hit:3 http://archive.canonical.com/ubuntu xenial InRelease
Hit:4 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial-backports InRelease
Hit:5 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial-security InRelease
Fetched 102 kB in 2s (38.2 kB/s)
Reading package lists... Done
ru12mug-the2nd@ru12mugthe2nd-Satellite-L300:~$ sudo apt-get install synaptic
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  gnome-video-effects linux-headers-4.4.0-47 linux-headers-4.4.0-47-generic
  linux-headers-4.4.0-51 linux-headers-4.4.0-51-generic linux-headers-4.4.0-53
  linux-headers-4.4.0-53-generic linux-image-4.4.0-47-generic
  linux-image-4.4.0-51-generic linux-image-4.4.0-53-generic
  linux-image-extra-4.4.0-47-generic linux-image-extra-4.4.0-51-generic
  linux-image-extra-4.4.0-53-generic
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
  libcairo-perl libept1.5.0 libglib-perl libgtk2-perl libpango-perl librarian0
  rarian-compat
Suggested packages:
  libfont-freetype-perl libgtk2-perl-doc dwww menu deborphan tasksel
The following NEW packages will be installed:
  libcairo-perl libept1.5.0 libglib-perl libgtk2-perl libpango-perl librarian0
  rarian-compat synaptic
0 to upgrade, 8 to newly install, 0 to remove and 0 not to upgrade.
Need to get 2,745 kB of archives.
After this operation, 13.5 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 libcairo-perl i386 1.106-1build1 [94.3 kB]
Get:2 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 libept1.5.0 i386 1.1+nmu3 [83.0 kB]
Get:3 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 libglib-perl i386 3:1.320-2 [340 kB]
Get:4 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 libpango-perl i386 1.227-1 [161 kB]
Get:5 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 libgtk2-perl i386 2:1.2498-1 [590 kB]
Get:6 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 librarian0 i386 0.8.1-6 [53.5 kB]
Get:7 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 rarian-compat i386 0.8.1-6 [57.8 kB]
Get:8 http://mirror.aarnet.edu.au/pub/ubuntu/archive xenial/universe i386 synaptic i386 0.83 [1,365 kB]
Fetched 2,745 kB in 7s (358 kB/s)
Selecting previously unselected package libcairo-perl.
(Reading database ... 335074 files and directories currently installed.)
Preparing to unpack .../libcairo-perl_1.106-1build1_i386.deb ...
Unpacking libcairo-perl (1.106-1build1) ...
Selecting previously unselected package libept1.5.0:i386.
Preparing to unpack .../libept1.5.0_1.1+nmu3_i386.deb ...
Unpacking libept1.5.0:i386 (1.1+nmu3) ...
Selecting previously unselected package libglib-perl.
Preparing to unpack .../libglib-perl_3%3a1.320-2_i386.deb ...
Unpacking libglib-perl (3:1.320-2) ...
Selecting previously unselected package libpango-perl.
Preparing to unpack .../libpango-perl_1.227-1_i386.deb ...
Unpacking libpango-perl (1.227-1) ...
Selecting previously unselected package libgtk2-perl.
Preparing to unpack .../libgtk2-perl_2%3a1.2498-1_i386.deb ...
Unpacking libgtk2-perl (2:1.2498-1) ...
Selecting previously unselected package librarian0.
Preparing to unpack .../librarian0_0.8.1-6_i386.deb ...
Unpacking librarian0 (0.8.1-6) ...
Selecting previously unselected package rarian-compat.
Preparing to unpack .../rarian-compat_0.8.1-6_i386.deb ...
Unpacking rarian-compat (0.8.1-6) ...
Selecting previously unselected package synaptic.
Preparing to unpack .../synaptic_0.83_i386.deb ...
Unpacking synaptic (0.83) ...
Processing triggers for man-db (2.7.5-1) ...
Processing triggers for libc-bin (2.23-0ubuntu5) ...
Processing triggers for doc-base (0.10.7) ...
Scrollkeeper was installed, forcing re-registration of all documents.
Unregistering 34 doc-base files, re-registering 35 doc-base files...
Error in `/usr/share/doc-base/xapian-python3-docs', line 9: all `Format' sections are invalid.
Note: `install-docs --verbose --check file_name' may give more details about the above error.
Registering documents with scrollkeeper...
Processing triggers for bamfdaemon (0.5.3~bzr0+16.04.20160824-0ubuntu1) ...
Rebuilding /usr/share/applications/bamf-2.index...
Processing triggers for gnome-menus (3.13.3-6ubuntu3.1) ...
Processing triggers for desktop-file-utils (0.22-1ubuntu5) ...
Processing triggers for mime-support (3.59ubuntu1) ...
Processing triggers for hicolor-icon-theme (0.15-0ubuntu1) ...
Setting up libcairo-perl (1.106-1build1) ...
Setting up libept1.5.0:i386 (1.1+nmu3) ...
Setting up libglib-perl (3:1.320-2) ...
Setting up libpango-perl (1.227-1) ...
Setting up libgtk2-perl (2:1.2498-1) ...
Setting up librarian0 (0.8.1-6) ...
Setting up rarian-compat (0.8.1-6) ...
Setting up synaptic (0.83) ...
Processing triggers for libc-bin (2.23-0ubuntu5) ...

Does this help. Thanks.

Furthermore, I suggest subscribing to the following bugreport:

https://bugs.launchpad.net/ubuntu/+source/xapian1.3-bindings/+bug/1581995

Thanks Mark. Now I'm off to do some reading and hopefully learning.

Thanks Mark Rijckenberg, that solved my question.