// REFERENCE
505 HTTP Version Not Supported
Class: 5xx
The server doesn't support the HTTP version of the request. It's rare today; it can appear with very old clients or malformed requests.
Related tools
Work with this in:
Related
500
500 Internal Server Error 501
501 Not Implemented 502
502 Bad Gateway 503
503 Service Unavailable 504
504 Gateway Timeout 511
511 Network Authentication Required
500 Internal Server Error 501
501 Not Implemented 502
502 Bad Gateway 503
503 Service Unavailable 504
504 Gateway Timeout 511
511 Network Authentication Required
Semantics per RFC 9110 and the IANA status code registry. Educational content.