426
426 Upgrade Required Error
What This Error Means
The 426 Upgrade Required error indicates that the server refuses to perform the request using the current protocol but might be willing to do so after the client upgrades to a different protocol. This is common with WebSocket connections.
Common Causes
- Client trying to use HTTP/1.1 when HTTP/2 is required.
- WebSocket handshake failure.
- API requiring TLS 1.2+ when client uses older version.
How to Fix It (For Users)
- 1 Update your browser or client software.
- 2 Ensure your network supports WebSockets.
For Site Owners / Developers
- Check your server's protocol upgrade settings.
- Ensure WebSocket headers (Upgrade, Connection) are passed correctly by proxies.
- Provide clear instructions on required protocols in API documentation.
When It Is NOT Your Fault
If the server requires a protocol your device does not support.
Check if this outage affects everyone globally
This error often indicates a wider problem. Use our tool to verify if the site is down for everyone.
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