510 Not Extended

This error response code is referenced in experimental technology (RFC 2774).

The response indicates the server does not support the request extension declaration. A client can send a request describing the extension they want to use, but in this case the extension is not supported by the server.

Most users will not see this error response.

Use of this error response is not recommended as there are alternative methods to RFC 2774 to receive similar effects.

There is no recommended troubleshooting for this error.

If the error persist contact the server support for help.

The HyperText Transfer Protocol (HTTP) 510 Not Extended response status code is sent in the context of the HTTP Extension Framework, defined in RFC 2774.

In that specification a client may send a request that contains an extension declaration, that describes the extension to be used. If the server receives such a request, but any described extensions are not supported for the request, then the server responds with the 510 status code.