ERR_HTTP2_PROTOCOL_ERROR
The HTTP/2 response was malformed or cut short
Seen in Chrome, Edge, Brave
The server sent HTTP/2 data the browser considered invalid, or the stream was reset part-way through the response.
Common causes
- The application sends an invalid header, such as one with illegal characters or a connection-specific header like "Connection" or "Transfer-Encoding".
- A reverse proxy truncated the response because it ran out of disk space for buffering or hit a timeout.
- A CDN, proxy or antivirus in the middle mangles HTTP/2 traffic.
How to fix it
- Check the web server and proxy error logs at the time of the request.
- Remove invalid or hop-by-hop headers from the application response.
- Free disk space and check permissions on proxy temp directories (e.g. nginx proxy_temp_path).
- Test with "curl --http2 -v" to see where the stream fails.
Got a different message? Paste it into the error explainer.
Related errors
- ERR_TOO_MANY_REDIRECTS · The page redirects in a loop
- ERR_CONNECTION_CLOSED · The server closed the connection unexpectedly
- ERR_EMPTY_RESPONSE · The server didn't send any data
- ERR_QUIC_PROTOCOL_ERROR · The HTTP/3 (QUIC) connection failed
- NET::ERR_CERT_DATE_INVALID · The certificate has expired or is not yet valid
- NET::ERR_CERT_AUTHORITY_INVALID · The certificate isn't issued by a trusted authority
- SEC_ERROR_UNKNOWN_ISSUER · Firefox doesn't recognise the certificate's issuer
- NET::ERR_CERT_COMMON_NAME_INVALID · The certificate doesn't cover this name
- ERR_SSL_PROTOCOL_ERROR · The secure connection failed during the handshake
- ERR_SSL_VERSION_OR_CIPHER_MISMATCH · No TLS version or cipher in common
- You cannot visit this site right now because the website uses HSTS · HSTS blocks the bypass of a certificate error
- NET::ERR_CERT_REVOKED · The certificate has been revoked by its issuer