Hello,
i use Joomla 3.4 (fresh install) and when i click button "save" on General configuration tab i have 404 error (Forbidden).
my domein is: namerete.3w-bg.org
php info: namerete.3w-bg.org/i.php

Dear Customer,

Actually the issue is your hosting is not allowing to save javascripts. So kindly remove (make empty) the Social Share script field in your Joomla admin under Jomclassifieds Configuration => Layout Settings and try to save.

Thanks.