Xubuntu 16.04 Software Updater not functioning anymore

[MR ZenWiz]

The GUI Software Updater is showing a red circle with the horizontal
white line (do not enter) icon on my notification area, I can't run it
through the main menu or the settings manager, and when I try to run
it form the command line, I get this:

admar at marbase:~/Downloads $ sudo apt-get update
Hit:1 http://security.ubuntu.com/ubuntu xenial-security InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu xenial InRelease
Hit:3 http://us.archive.ubuntu.com/ubuntu xenial-updates InRelease
Hit:4 http://us.archive.ubuntu.com/ubuntu xenial-backports InRelease
Reading package lists... Done
admar at marbase:~/Downloads $ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
3 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up update-notifier-common (3.168.3) ...
Traceback (most recent call last):
  File "/usr/lib/update-notifier/package-data-downloader", line 26, in <module>
    import debconf
ImportError: No module named 'debconf'
dpkg: error processing package update-notifier-common (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of flashplugin-installer:
 flashplugin-installer depends on update-notifier-common (>=
0.119ubuntu2); however:
  Package update-notifier-common is not configured yet.

dpkg: error processing package flashplugin-installer (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a
followup error from a previous failure.

                                   dpkg: dependency problems prevent
configuration of update-notifier:
 update-notifier depends on update-notifier-common (= 3.168.3); however:
  Package update-notifier-common is not configured yet.

dpkg: error processing package update-notifier (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a
followup error from a previous failure.

                                   Errors were encountered while
processing:
 update-notifier-common
 flashplugin-installer
 update-notifier
E: Sub-process /usr/bin/dpkg returned an error code (1)

I tried to purge them and reinstall, but I get the same errors.

What happened (and how do I fix this)?

Thanks.
MR