Bug#733948: hplip-gui: HP Toolbox can't be used as regular user when root account disabled
After closer examination, during installation when I choose to disable
the root account by specifying a blank password, the admin user created
is not added to the lpadmin group.
Adding the user to the lpadmin group makes it possible to then run
hp-toolbox from command line as such user, and the printer is added as
expected:
sudo adduser $USER lpadmin
It's necessary to logout and login again for this to take effect.
Reply to: