Code 601

The `code 601` error indicates that the audio and video stream connection between the client and the rendering server could not be established. This is typically caused by blocked network ports or an incompatible browser that does not support WebRTC.

## Cause 1: Audio and Video Ports Are Blocked

For users accessing the rendering service over an external network (extranet), the required UDP port range must be open on the rendering server's firewall or router. If these ports are blocked, the audio and video stream cannot be transmitted, resulting in a `code 601` error.

### Solution

Open the **Rendering Service Manager** and ensure that the required UDP port range is properly configured and accessible from the public network. Refer to the following guide for detailed configuration steps:

[How to Configure Public Network Access](https://www.pingxingyun.com/online/sr3_2.html?id=442)

## Cause 2: The Browser Does Not Support WebRTC

LarkXR's web client relies on WebRTC for real-time audio and video transmission. If the user's browser does not support WebRTC, the stream connection cannot be established.

### Solution

Ensure that the user is accessing the web client using a supported browser. Refer to the following list for compatible browsers:

[Supported Browsers List](https://www.pingxingyun.com/online/sr3_2.html?id=397)

## Notes

- UDP ports must be accessible from the client's network. Firewalls, NAT configurations, or ISP restrictions may block UDP traffic and should be checked if the issue persists.
- Always use a WebRTC-compatible browser (such as Google Chrome or Microsoft Edge) for the best compatibility with LarkXR's web client.