When you try to add printer you might get the following error message

Solution
This is known bug#871985
WORKAROUND: As an alternative to the printer configuration tool from the new Gnome Shell control center, you can still use system-config-printer. To open it, just press Alt+F2, type system-config-printer and press Enter.
Incoming search terms:
- firewalld is not running
- Firewalld
- ubuntu firewalld
- firewalld ubuntu
- firewalld not running
- ubuntu firewalld is not running
- firewalld is not running ubuntu
- linux firewalld
- ubuntu 12 04 firewalld is not running
- ubuntu printer firewalld is not running





Please use the command to add a new printer:
system-config-printer
[Reply]
this is not ‘how to fix,’ this is a workaround.
[Reply]
Thanks. This worked around the problem for me too. How can I fix the actual problem? What is this Firewalld business? I am using Zorin OS6
[Reply]
This worked for me, a very good alternative! This “bug” appears in Ubuntu 12.4. It does not handle multiple printers available on the local network very well. Auto-identifies a Brother as an HP. The HP is turned off.
[Reply]