404. That’s an error.
The requested URL /add?feedurl=http://mfxmjmjj.no6.35nic.com/cn/rss/rss_downs.xml was not found on this server. That’s all we know.
/add?feedurl=http://mfxmjmjj.no6.35nic.com/cn/rss/rss_downs.xml