I just got my new Raspberry Pi 2 and installed RASPBIAN using NOOBs.

On start up I get this error. Its in a message box in the middle of the screen. If I hit ok the GUI seems to work find anyway.

GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: Cannot determine user of subject

I have looked around and for similar errors people suggest this to fix the problem

Preferences->Desktop Session Settings" and un-check "PolicyKit Authentication Agent"

However there is no "Preferences->Desktop Session Settings" that I can find.

Does anyone else with a raspberry Pi 2 have this problem with a fresh install of RASPBIAN? Or do you know where I can find these Preferences.


  • Same here. Two units, both gave the same error message on first use of startx. Both do not show the error on subsequent starts.
    – user26939
    Commented Feb 12, 2015 at 17:11

1 Answer 1

  1. Open LXTerminal.
  2. Type lxsession-edit to open Desktop Session Settings dialog box.
  3. Uncheck LXPolKit.
  4. Click OK.
  5. Reboot.

If no LXPolKit option then try this :

  1. Open Terminal.
  2. Type sudo leafpad /etc/xdg/autostart/lxpolkit.desktop
  3. Add the text LXDE to the line NotShownIn
  4. The line should read: NotShowIn=GNOME;KDE;LXDE. Save the file afterwards.

The lx policy kit still runs, it just doesn't report errors ...

  • Thanks skipmonkey that was the window I was looking for :)
    – Chris
    Commented Feb 12, 2015 at 23:54
  • I started seeing this error after installing xrdp, this advice fixed it though. Thanks ^_^
    – PiBorg
    Commented Mar 25, 2015 at 17:04
  • I don't have the LXPolKit item in that window. I show Blueman Applet, GSettings Data Conversion, LXInput autostart, lxkeymap, and Notification Daemon. Everything except GSettings Data Conversion is checked. Any other suggestions? Thanks.
    – Stickhog
    Commented Dec 11, 2015 at 18:20
  • in my system i didn't see the policykit setting in Desktop Session Settings. so only after installing this package "policykit-1-gnome" i saw it and could disable it.
    – Asaf Magen
    Commented Mar 19, 2016 at 20:23

Not the answer you're looking for? Browse other questions tagged or ask your own question.