510 Not Extended

This is an educational reference page about HTTP 510 Not Extended. The page itself is served as 200 OK so it can be indexed as HTTP documentation.

Further extensions to the request are required for the server to fulfill it.

Specification

Registered in the IANA HTTP Status Code Registry as Not Extended (OBSOLETED). Defined in RFC 2774, Section 7.

The IANA registry marks 510 as obsoleted. The HTTP Extension Framework in RFC 2774 has been moved to Historic status.

5xx server error – the server failed to fulfill an apparently valid request