404. That’s an error.

The requested URL /custom?q=%22mark+ring%22&client=google-coop-np&cof=FORID:13%3BAH:left%3BS:http://www.emacswiki.org/%3BCX:Emacs%2520Wiki%2520Search%3BL:http://www.emacswiki.org/emacs_rss.png%3BLH:43%3BLP:1%3BVLC:%23551a8b%3BDIV:%23cccccc%3B&cx=004774160799092323420:6-ff2s0o6yi&adkw=AELymgWGmwNQXnnjSze7ShzUno1fDisMhdh5eij6xpfrsetE9in2RPC68xa9t5_F3QsXtPgLCyle1Bd343DEmpoKGgPajN737i2Hm057KmTnvdchvjMgrKQ&hl=en&boostcse=0&ie=UTF-8&oe=UTF-8&prmd=ivns&ei=7OoTVri0NYSo-QGrnb_ABA&start=10&sa=N was not found on this server. That’s all we know.