RingCentral's official JavaScript WebRTC SDK (407 Proxy Authentication Required)

  • 5 January 2023
  • 1 reply


My problem is related to RingCentral's official JavaScript WebRTC SDK (

The issue is that I can't make calls to external phone numbers (I believe), for example when I place a call to +18002758777 (USPS), I can't hear anything on the audio channel and in the logs I can see "407 Proxy Authentication Required" websocket message from the SIP Transport. This happens for all the public phone numbers I find on the Internet. However, I can successfully call my other user.

Also, this doesn't happen when I call the phone number using the RingCentral app.

I couldn't find any information about this in the docs or in the Community.

Is this a matter of a configuration in the Admin Portal? I couldn't find any settings there that could be related to this issue.

1 reply

I tried the official demo I could successfully call 18002758777.

Could you please try it? If it works, the the root cause might be in your own code. If it doesn't work, then it might be your account's configuration issue.