Linux Mint 19 x64 with Cinnamon
Whenever I try to install a .deb by double clicking the file and clicking "Install Package" on the Package Installer popup, I get the following error:
There seems to be a programming error in aptdaemon, the software that allows you to install/remove software and to perform other package management related tasks.
org.freedesktop.DBus.Error.NoReply: Message recipient disconnected from message but without replying.
I can run
apt update and
upgrade just fine. I think something went wrong with an install I did awhile back using
dpkg from the command line. I cannot find any details about how to fix this. Any ideas?
EDIT: I also can't install things from the Software Manager GUI. I've tried reinstalling both
gdebi but my situation has not changed after doing so. Can't uninstall through the GUI either.
EDIT 2: I've found that I can't open synaptic from the menu. If I run
synaptic-pkexec from the command line I get the following output:
Error checking for authorization com.ubuntu.pkexec.synaptic: GDBus.Error:org.freedesktop.DBus.Error.NoReply: Message recipient disconnected from message bus without replying
Which leads me to think my problem might have to do with policykit but I don't know enough about policykit.
policykit-desktop-privileges seems to an aid for users in the admin or sudo groups that run common tasks as sudo for them automatically. When I double click a deb file and the gdebi-gtk no problem arises until it would normally ask for my sudo password.
How do I troubleshoot potential issues with policykit?
EDIT 3: The problem seems to be rooted in Policy Kit so I've edited the question. I have a stable install of Linux Mint 19 x64 on my laptop and have been comparing my desktop's behavior to the laptop. On my laptop I run
pkexec nano and the UI pops up asking for my password for sudo and running nano when I give the password. On my server, where I'm having the problem, when I run
pkexec nano instead of the UI popup I expect, I get the same output I get when running
synaptic-pkexec (except it says com.ubuntu.pkexec.exec instead of synaptic).
From some googling it seems that the default policy kit is supposed to be
/usr/lib/policykit-1-gnome/polkit-gnome-authentication-agent-1. When I run the file I get:
** (polkit-gnome-authentication-agent-1:13684): WARNING **: 10:10:40.701: Unable to register authentication agent: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: An authentication agent already exists for the given subject
I'm not sure if there's a way to find what is the current authentication agent. I do have a service called
polkit that's active and doesn't seem to be throwing any errors. I've checked the log in
/var/log/auth.log but it doesn't contain any errors. When I do the above
pkexec nano the log prints the following:
Aug 9 10:14:44 MyComputerName polkitd(authority=local): Registered Authentication Agent for unix-session:c2 (system bus name :1.56 [/usr/lib/policykit-1-gnome/polkit-gnome-authentication-agent-1], object path /org/gnome/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8)
This feels like polkit-gnome-authentication-agent-1 is active and running but apparently improperly.
I also find it weird that I can run
sudo apt update and get prompted for my password properly (and it executes properly when given the password). I thought polkit would be in charge of that and it seems broken.