511 Network Authentication Required

This error response indicates the client must authenticate to gain network privileges. Network operators may

510 Not Extended

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

508 Loop Detected

This error response is designed for WebDAV purposes, but in some cases may appear elsewhere.

507 Insufficient Storage

This error response is designed for WebDAV purposes, but in some cases may appear elsewhere.

506 Variant Also Negotiates

This error applies to an experimental technology, Transparent Content Negotiation (RFC 2295). This relates to

505 HTTP Version Not Supported

This error response indicates the server does not support HTTP version used in the client

504 Gateway Timeout

This server error indicates a gateway, or proxy, server did not receive a response within

503 Service Unavailable

This response indicates that server is not in a state to process requests. Usually this

502 Bad Gateway

This error response indicates the server is acting as a gateway, or proxy, and received

501 Not Implemented

This response error indicates the server doesn’t recognize the request method and cannot support it.