topic Registered
Verified 2026-09-19 · registry updated
2022-08-17HTTP registry: 0x0c
Negotiated TLS parameters not acceptable
HTTP/2 registry values apply to binary framing, stream state, connection setup, or protocol negotiation. 0x0c is registered in HTTP/2 Error Code. Defining reference: RFC9113, Section 7.
httpregistryhttp2-parameterserror-code
Identifier (http)
0x0c
Negotiated TLS parameters not acceptable
Do not serialize HTTP/2 control values as ordinary HTTP/1.1 fields; let a compliant stack enforce ordering, stream state, and bounds.
This registry value is currently marked active by IANA. Follow the defining specification before sending, accepting, or proxying it.
IANA registry: http2-parameters/error-code
Registry reference: RFC9113, Section 7