sf-maintenance Error Code Error Name Description 400 Bad Request Invalid request sent by client 401 Unauthorized Authentication required for access 403 Forbidden Access to resource is restricted 404 Not Found Requested resource not available 405 Method Not Allowed HTTP method is not supported 406 Not Acceptable Unacceptable response format 407 Proxy Authentication Required Proxy authentication is required 412 Precondition Failed Request conditions not satisfied 414 Request-URI Too Long URI exceeds allowed length limit 415 Unsupported Media Type Media type not supported by server 500 Internal Server Error Server encountered unexpected issue 501 Not Implemented Server lacks requested functionality 502 Bad Gateway Invalid response from upstream server 503 Maintenance Server temporarily unavailable