Comment 0 for bug 2063050

Seems like it might be related to Bug #2049785, although that appears to have been fixed.

Update manager GUI no longer works after enabling Ubuntu Pro. Manually updating via CLI is fine. There seem to be other issues with the pro tools as well.

$ update-manager

(update-manager:6577): dbind-WARNING **: 19:31:44.465: Couldn't register with accessibility bus: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
WARNING:root:can not import unity GI Namespace Dbusmenu not available
Unexpected error(s) occurred.
For more details, see the log: /var/log/ubuntu-advantage.log
To file a bug run: ubuntu-bug ubuntu-advantage-tools
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/UpdateManager/backend/InstallBackendAptdaemon.py", line 248, in _on_finished
    trans_failed=trans_failed)
  File "/usr/lib/python3/dist-packages/UpdateManager/backend/__init__.py", line 95, in _action_done
    self.window_main.start_available(is_cancelled_update)
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdateManager.py", line 242, in start_available
    self.refresh_cache()
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdateManager.py", line 442, in refresh_cache
    self._get_ua_security_status()
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdateManager.py", line 264, in _get_ua_security_status
    s = json.load(p.stdout)
  File "/usr/lib/python3.6/json/__init__.py", line 299, in load
    parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
  File "/usr/lib/python3.6/json/__init__.py", line 354, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.6/json/decoder.py", line 339, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.6/json/decoder.py", line 357, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: update-manager 1:18.04.11.23
ProcVersionSignature: Ubuntu 4.15.0-224.236-generic 4.15.18
Uname: Linux 4.15.0-224-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.29
Architecture: amd64
CurrentDesktop: MATE
Date: Sun Apr 21 19:29:27 2024
PackageArchitecture: all
SourcePackage: update-manager
UpgradeStatus: Upgraded to bionic on 2018-05-15 (2168 days ago)