4074xx Client error
SIP 407 Proxy Authentication Required
Usually sent by A proxy
What it means
The same idea as 401, but the challenge comes from a proxy rather than the destination. Your device must answer with a Proxy-Authorization header and resend.
SIP/2.0 407 Proxy Authentication Required
Common causes
- First request through a proxy that requires authentication
- Wrong credentials or realm for the proxy
- The device is not answering the proxy challenge
How to fix it
- Resend with a Proxy-Authorization header using the correct credentials
- Confirm the username, password and realm match what the proxy expects
- Check your device handles proxy challenges automatically
See it in your own trace
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