/etc/dbus-1/system.d/ Current File: //etc/dbus-1/system.d/com.ubuntu.SoftwareProperties.conf

<!DOCTYPE busconfig PUBLIC
 "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>

  <policy user="root">
    <allow own="com.ubuntu.SoftwareProperties"/>
  </policy>

  <policy context="default">
    <allow send_destination="com.ubuntu.SoftwareProperties"
           send_interface="com.ubuntu.SoftwareProperties"/>
    <allow send_destination="com.ubuntu.SoftwareProperties"
           send_interface="org.freedesktop.DBus.Introspectable"/>
    <allow send_destination="com.ubuntu.DeviceDriver"
           send_interface="org.freedesktop.DBus.Properties"/>
  </policy>

</busconfig>