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5xx Server Error
505
HTTP Version Not Supported
The server does not support the HTTP version used in the request.
What it means
A 505 HTTP Version Not Supported response indicates the server does not support the HTTP protocol version used in the request.
Common causes
- The client used an HTTP version the server cannot handle.
- Protocol version mismatch between client and server.
How to fix it
- Use an HTTP version supported by the server, typically HTTP/1.1 or HTTP/2.
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