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# SIP Call Error Handling Updates

The following specific SIP error codes have been added to help identify call failures:

* `call.in-progress.error-sip-inbound-call-failed-to-connect`
* `call.in-progress.error-providerfault-outbound-sip-403-forbidden`
* `call.in-progress.error-providerfault-outbound-sip-407-proxy-authentication-required`
* `call.in-progress.error-providerfault-outbound-sip-503-service-unavailable`
* `call.in-progress.error-providerfault-outbound-sip-480-temporarily-unavailable`
* `call.in-progress.error-sip-outbound-call-failed-to-connect`
* `call.in-progress.error-vapifault-worker-died`

> **Warning**
>
> The generic error code `call.in-progress.error-sip-telephony-provider-failed-to-connect-call` has been removed. Update your error handling to use the new specific error codes instead.