Really thanks.
Could I know what is changed?
I suppose some code in some file.
I mean, was it some plugins or component that caused that error?

Hi,

please go to plugins/system/x_menu_params/x_menu_params.php
and find:

if($data['id'] && $data['parent_id'] == 1) {

=> change to:

if (is_object($data))
{ $data = (array)$data; }
if($data['id'] && $data['parent_id'] == 1) {

thanks