ERR_NGROK_2229: Failed to validate Traffic Policy for unknown protocol PROTO.'

What does ERR_NGROK_2229 mean?

ngrok returns ERR_NGROK_2229 with this message:

Failed to validate Traffic Policy for unknown protocol <PROTO>.'

Troubleshoot ERR_NGROK_2229 with your AI agent. Connect it to the ngrok MCP server, then ask what caused the error and how to fix it.

Email support@ngrok.com and include the error code.