I tried gnome3 and gnome3-staging ppas to test running Gnome 3.8. After a while I decided that Gnome 3.8 wasn't for me, so I did a ppa-purge of both the ppas. As described in
gnome3-staging ppa page, I also did:
$ sudo apt-get purge libpam-systemd $ sudo apt-get install libpam-xdg-support
The trouble is, I can't mount my external USB device anymore. When I try to mount it as a user, it fails:
$ udisks --mount /dev/sdc1 Mount failed: Not Authorized
I am logged in an XFCE session, but the same thing happens in a fallback Gnome session, or from a Unity session. Also, in XFCE, "suspend" and "shut down" menus are grayed out.
I can't also open synaptic package manager from XFCE menus (
sudo synaptic works).
After a lot of searching, it seems like it is a policykit issue. I see the following in my
(polkit-gnome-authentication-agent-1:5805): polkit-gnome-1-WARNING **: Unable to determine the session we are in: No session for pid 5805
PID 5805 doesn't exist. If I try to start
polkit-dnome-authentication-agent-1 from an xterm, I get the same error (different PID):
$ /usr/lib/policykit-1-gnome/polkit-gnome-authentication-agent-1 ... (polkit-gnome-authentication-agent-1:15971): polkit-gnome-1-WARNING **: Unable to determine the session we are in: No session for pid 15971
... lines are warnings from GTK about missing css files etc.).
polkitd is running:
$ pidof polkitd 1495
Is there something I am missing?