I use gnome desktop on Ubuntu 18.04. I want to delete a printer and rename another.
I would like to use the GUI under settings and devices to administer my printers.
Help page advice me to: "Click the Unlock button in the top-right corner and enter your password." But the Unlock button is not active. When hovering the mouse pointer above the button, it tells me that system policy prevents it, and that I should contact my system administrator.
How do I fix this?
I cannot unlock the button under users either. But in "Users Administration Tool" I am set to be administrator.
I found this post 12.04 - Cannot unlock user account although it is an admin accountand executed this command:
ps -ef | grep [p]olkit
root 993 1 0 aug22 ? 00:00:04 /usr/lib/policykit-1/polkitd --no-debugBut I don't know what to look for.
44 Answers
Does not exactly cover the problem of this question (disabled unlock button with no obvious way to enable) but for the purposes of adding/deleting/renaming a printer, you could do
me$ sudo su
root$ system-config-printer(I believe you can straight-up sudo system-config-printer but something in my machine made that not work.)
From the dialog that opens you can right click on existing printers to delete or rename them.
2If you have google chrome remote desktop installed, try uninstalling that to resolve your issue.
For me, I was having the same issue, and uninstalling the chrome remote desktop solved it. I don't know but somehow, it interferes with the settings. –
2On Fedora 34 at least, the software with the GUI printer settings is called gnome-control-center. I can confirm that starting it as root with sudo gnome-control-center fixed the disabled "Unlock" button and I was able to add my printer as described in the opensource.com Common Unix Printing System (CUPS) docs. Exiting and re-starting the print dialog resulted in the printer showing up as a target.
As an additional security measure, you need to log in to a physical seat to be able to unlock under the default configuration. If that is impossible, e.g. when the machine is virtual, you need to change the policies from ResultActive to ResultAny.
