Traceback (most recent call last):
  File "/usr/share/gufw/gufw.py", line 30, in <module>
    controler = Controller()
  File "/usr/share/gufw/controller.py", line 24, in __init__
    self.firewall = Firewall()
  File "/usr/share/gufw/model/Firewall.py", line 33, in __init__
    remote_object = bus.get_object("gufw.Daemon", "/Gufw_daemon")
  File "/usr/lib/pymodules/python2.7/dbus/bus.py", line 244, in get_object
    follow_name_owner_changes=follow_name_owner_changes)
  File "/usr/lib/pymodules/python2.7/dbus/proxies.py", line 241, in __init__
    self._named_service = conn.activate_name_owner(bus_name)
  File "/usr/lib/pymodules/python2.7/dbus/bus.py", line 183, in activate_name_owner
    self.start_service_by_name(bus_name)
  File "/usr/lib/pymodules/python2.7/dbus/bus.py", line 281, in start_service_by_name
    'su', (bus_name, flags)))
  File "/usr/lib/pymodules/python2.7/dbus/connection.py", line 630, in call_blocking
    message, timeout)
DBusException: org.freedesktop.DBus.Error.Spawn.ChildExited: Launch helper exited with unknown return code 1