software-properties-gtk fails to open with error

[cprecht2123]

When trying to open software-properties-gtk via Terminal (via GUI: “Settings & Livepatch”) the following error is returned in the terminal and software-properties-gtk does not open.

ERROR:dbus.proxies:Introspect error on :1.121:/: dbus.exceptions.DBusException: org.freedesktop.DBus.Error.NoReply: Message recipient disconnected from message bus without replying
Traceback (most recent call last):
  File "/usr/bin/software-properties-gtk", line 100, in <module>
    app = SoftwarePropertiesGtk(datadir=options.data_dir, options=options, file=file)
  File "/usr/lib/python3/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py", line 211, in __init__
    self.backend.Reload();
  File "/usr/lib/python3/dist-packages/dbus/proxies.py", line 72, in __call__
    return self._proxy_method(*args, **keywords)
  File "/usr/lib/python3/dist-packages/dbus/proxies.py", line 141, in __call__
    return self._connection.call_blocking(self._named_service,
  File "/usr/lib/python3/dist-packages/dbus/connection.py", line 652, in call_blocking
    reply_message = self.send_message_with_reply_and_block(
dbus.exceptions.DBusException: org.freedesktop.DBus.Error.ServiceUnknown: The name :1.121 was not provided by any .service files

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: software-properties-gtk 0.98.9.2
ProcVersionSignature: Ubuntu 5.4.0-51.56-generic 5.4.65
Uname: Linux 5.4.0-51-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.9
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Fri Oct 16 08:17:15 2020
InstallationDate: Installed on 2020-10-09 (6 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
PackageArchitecture: all
SourcePackage: software-properties
UpgradeStatus: No upgrade log present (probably fresh install)

[cprecht2123 (cprecht2123)]

It appears that this command did the trick (took it from here: https://askubuntu.com/questions/1171211/ubuntu-18-04-software-properties-gtk-failing-with-org-freedesktop-dbus-error-ser).

sudo apt-get update && sudo apt-get install --reinstall python3-six python3-certifi

Would be nice to have a professional explanation of what was "messed up". Thanks!

[Sebastien Bacher (seb128)]

Thank you for your bug report. Could you add your journalctl log from a session where you had the issue? ('journalctl -b <n>' get you the log from 'n' system restart ago)
Did the command install packages that were missing? If so do you have any idea where those were not installed?

[Launchpad Janitor (janitor)]

[Expired for software-properties (Ubuntu) because there has been no activity for 60 days.]

[Christian Rauch (christianrauch)]

I encountered the same error (see duplicate https://bugs.launchpad.net/ubuntu/+source/software-properties/+bug/1930974/comments/5) and was able to resolve the issue by reinstalling packages "python3-six" and "python3-certifi" as suggested in https://bugs.launchpad.net/ubuntu/+source/software-properties/+bug/1900098/comments/2. Those packages were installed before.

The relevant journalctl section is:

May 18 18:45:47 gungnir dbus-daemon[1746]: [system] Activating service name='com.ubuntu.SoftwareProperties' requested by ':1.7781' (uid=1000 pid=497419 comm="/usr/bin/python3 /usr/bin/software-properties-gtk " label="unconfined") (using servicehelper)
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: Unable to init server: Could not connect: Connection refused
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: Unable to init server: Could not connect: Connection refused
May 18 18:45:48 gungnir dbus-daemon[1746]: [system] Successfully activated service 'com.ubuntu.SoftwareProperties'
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: Traceback (most recent call last):
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/usr/lib/software-properties/software-properties-dbus", line 68, in <module>
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: server = SoftwarePropertiesDBus(bus, datadir=datadir)
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/lib/python3/dist-packages/softwareproperties/dbus/SoftwarePropertiesDBus.py", line 66, in __init__
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: self._livepatch_service = LivepatchService()
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/lib/python3/dist-packages/softwareproperties/LivepatchService.py", line 93, in __init__
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: self._session = requests_unixsocket.Session()
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: NameError: name 'requests_unixsocket' is not defined
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: Error in sys.excepthook:
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: Traceback (most recent call last):
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/lib/python3/dist-packages/apport_python_hook.py", line 72, in apport_excepthook
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: from apport.fileutils import likely_packaged, get_recent_crashes
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/lib/python3/dist-packages/apport/__init__.py", line 5, in <module>
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: from apport.report import Report
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/lib/python3/dist-packages/apport/report.py", line 32, in <module>
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: import apport.fileutils
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]: File "/lib/python3/dist-packages/apport/fileutils.py", line 12, in <module>
May 18 18:45:48 gungnir com.ubuntu.SoftwareProperties[497432]:...

[Pablo (pmtomeo)]

I tried reinstalling all the packages, even the python ones and nothing worked. So I read the code in /lib/python3/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py and commenting out line 222 everything worked again!!! self.backend.Reload(); --> # self.backend.Reload();