ERR_NGROK_3004

Message

ngrok gateway error The server returned an invalid or incomplete HTTP response.

Further help

If you're having trouble resolving this error, please reach out to support@ngrok.com.

Additional Information

This error usually occurs when users are hosting a secure upstream service (https://localhost:[PORT]) but have not configured the ngrok agent to send HTTPS traffic to it.

Possible Solutions

When starting the ngrok agent, use the full upstream service address. For example: ngrok http https://localhost:8081.

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