404. That’s an error.
The requested URL /add?feedurl=http%3A%2F%2Fwww.rssmix.com%2Fu%2F8167002%2Frss.xml was not found on this server. That’s all we know.
/add?feedurl=http%3A%2F%2Fwww.rssmix.com%2Fu%2F8167002%2Frss.xml