404. That’s an error.
The requested URL /add?source=atgs&feedurl=http%3A//xn--xck8ai7jc8hb.seesaa.net/index.rdf was not found on this server. That’s all we know.
/add?source=atgs&feedurl=http%3A//xn--xck8ai7jc8hb.seesaa.net/index.rdf