404. That’s an error.
The requested URL /add?moduleurl=http://www.google.com/coop/api/013797765887759200806/cse/g0tuczwlta8/gadget was not found on this server. That’s all we know.
/add?moduleurl=http://www.google.com/coop/api/013797765887759200806/cse/g0tuczwlta8/gadget