Update-Manager and AptDeamon crashes - Ubuntu 14.04

[Gabriele Cesa]

update-manager, when launched, prints some stacktrace errors but keeps working. However, when I push 'install' button it shows only an empty gray frame and prints other errors, ending in:

<i>dbus.exceptions.DBusException: org.freedesktop.DBus.Error.NameHasNoOwner: Could not get owner of name 'org.debian.apt': no such name</i>

I found this similar (although not identical) problem: https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/1539847

I found other similar problems online and in most of the cases it was suggested to do and apt-get update, dist-upgrade and/or upgrade or to reinstall different packages through aptitude (mainly aptdaemon, dbus or update-manager)
However, after trying this solutions nothing changed.

Someone said that they had found a temporary solution running 'sudo aptd' in another terminal window and then opening 'update-manager'. Trying this solution and running 'sudo aptd' I get the following stack trace:

Traceback (most recent call last):
  File "/usr/sbin/aptd", line 37, in <module>
    import aptdaemon.core
  File "/usr/lib/python3/dist-packages/aptdaemon/core.py", line 66, in <module>
    from .worker import (
  File "/usr/lib/python3/dist-packages/aptdaemon/worker.py", line 56, in <module>
    import pkg_resources
  File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 72, in <module>
    import packaging.requirements
  File "/usr/local/lib/python3.4/dist-packages/packaging/requirements.py", line 59, in <module>
    MARKER_EXPR = originalTextFor(MARKER_EXPR())("marker")
TypeError: __call__() missing 1 required positional argument: 'name'

I tried reinstalling aptdeamon and python3.4 without results.

What I expected to happen: update-manager succeded to install packages and no stacktrace is printed on the terminal

System Informations:
Linux 3.19.0-80-generic #88~14.04.1-Ubuntu x86_64 x86_64 x86_64 GNU/Linux
Ubuntu 14.04.5 LTS

Other info:
apt-get, synaptic packet manager and Ubuntu Softwar Center seem to work properly

aptdaemon 1.1.1-1ubuntu5.2
update-manager 1:0.196.23
python3 3.4.0

If more informations are needed, I will be happy to provide any.

Thanks in advance

[Launchpad Janitor (janitor)]

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

[Sylvain GRIALOU (sylvouche2)]

Hi,
after a switch to "devel" from stable this happens (i think) because it would never be a complete update.