Transferring Inbound calls to external numbers failing on V20

[Liam-SiLANT]

Good morning,
I have an issue that we can't seem to resolve. I am trying to set up a function when the reception phone is on DND, it forwards the incoming calls to an external number. The forwarding works when an internal number calls, but when an inbound caller gets forwarded, it fails saying that your call could not be connected at this time. This happens on any inbound number that is transferred to any external number and we can't seem to fix it. This also happens when transferring inbound calls manually to an outside number.

We have contacted the phone line provider and they believe it has something to do with the server as they can't see anything on their end attempting to transfer the call. Attached is a pdf of the server logs (with some redacted info for security) when on a call and trying to transfer manually from the reception phone.

Does anyone have an idea what to try, we haven't had this issue on any V18 servers that use the same phone line provider as well.

 

[Guillaume Bourgeois]

Conduct a "capture" (Wireshark), starting the capture before replicating the issue, and then open it with Wireshark on your desktop computer.

Navigate to "Telephony" in the top menu, then select "VOIP Calls."

This will display a list of calls made and received during the capture period.

Locate and single-click on the call related to the issue, then click on "Flow Sequence."

This will provide a clear visual of your call's behavior.

Feel free to share a screenshot for our review, making sure to obscure any confidential information.

 

[Liam-SiLANT]

We've managed to figure it out after trying a lot of different combinations.

There seems to be an issue with V20 where if an inbound call is picked up by the digital receptionist first and then handed off to an extension. When the extension (for example reception) tries to transfer this inbound call to an outside number it will fail as there seems to be too many hops that the inbound phone call has made. We also discovered that we had to turn on call deflection for the DND call forwarding to work.

We have disabled the digital receptionist for now.

 

[Guillaume Bourgeois]

We've managed to figure it out after trying a lot of different combinations.

There seems to be an issue with V20 where if an inbound call is picked up by the digital receptionist first and then handed off to an extension. When the extension (for example reception) tries to transfer this inbound call to an outside number it will fail as there seems to be too many hops that the inbound phone call has made. We also discovered that we had to turn on call deflection for the DND call forwarding to work.

We have disabled the digital receptionist for now.

It sounds like an Outbound Rule is configured to only allow outgoing calls from internal extensions.

Please share your Outbound Rules. I'm convinced there's no rule allowing outgoing calls based on the number of digits dialed without restriction by extension number.

Could you describe your scenario using fictitious numbers, in the same format as your 3CX call log?

For example, you could describe your scenario like this:
When +18191111111 calls our DID +18197777777, the IVR 801 answers and transfers the call to extension 304, which is in Available status. If there's no answer, it forwards the call to the mobile number +18193333333, but fails and the call hangs up.