No authentication agent found for pkexec

I have an Ubuntu 16.04 headless system that I recently installed xfce4 and vnc4server onto. I can connect via VNC and see the desktop, but trying to launch privileged apps such as Synaptic silently fails.

Checking the synaptic.desktop entry shows use of synaptic-pkexec, which is just a small wrapper script for using pkexec.

Running the desktop entry directly shows the issue:

$ pkexec --disable-internal-agent "/usr/sbin/synaptic" "$@"
Error executing command as another user: No authentication agent found.

Question is - how do I resolve this? I'm new to PolicyKit, and I'm a bit surprised that apt install xfce4 apparently did not setup an authentication agent. Or perhaps I'm not automatically starting the desktop properly - here's my startup script:

~$ cat .vnc/xstartup
#!/bin/sh
# Uncomment the following two lines for normal desktop:
# unset SESSION_MANAGER
# exec /etc/X11/xinit/xinitrc
[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid grey
vncconfig -iconic &
# x-terminal-emulator -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" &
x-window-manager &
startxfce4 &

1 Sorted by: Reset to default

Know someone who can answer? Share a link to this question via email, Twitter, or Facebook.

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password Submit

Post as a guest

Post Your Answer Discard

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy