505 HTTP Version Not Supported
5xx Server Error
RFC 9110
The HTTP version in your request isn't supported here.
What 505 HTTP Version Not Supported means {#what}
The server doesn’t support the major HTTP version used in the request. Rarely encountered in practice — modern servers handle multiple HTTP versions gracefully.
When you’ll see a 505 {#when}
- Very old or very custom HTTP clients
- Misconfigured server environments