If the sender flags a D-Bus message as not expecting a reply, it is against system bus policy to send a reply — sending one will result in errors being sent to us by dbus-daemon. Magically drop all replies to messages which request no reply. This is not a complete fix. In an ideal world, the existing check for G_DBUS_METHOD_FLAG_NOREPLY would be dropped, as the server should be prepared to return a reply to every method, if the client requests and expects one — otherwise the client will time out. However, that’s a much bigger change with a much bigger risk of breaking things, so I’ll stick with this for now. Signed-off-by: Philip Withnall <philip.withnall(a)collabora.co.uk&gt; Reviewed-by: Simon McVittie <simon.mcvittie(a)collabora.co.uk&gt; ---  gdbus/object.c | 3 ++-  1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/gdbus/object.c b/gdbus/object.c index 96db516..146a255 100644 --- a/gdbus/object.c +++ b/gdbus/object.c @@ -258,7 +258,8 @@ static DBusHandlerResult process_message(DBusConnection *connection,     reply = method->function(connection, message, iface_user_data);   - if (method->flags & G_DBUS_METHOD_FLAG_NOREPLY) { + if (method->flags & G_DBUS_METHOD_FLAG_NOREPLY || +     dbus_message_get_no_reply(message)) {   if (reply != NULL)   dbus_message_unref(reply);   return DBUS_HANDLER_RESULT_HANDLED; -- 2.5.0