In-Reply-To header Pass Caller ID on call transfer - Callcentric [SOLVED]

[litmount (Randy Risser)]

Hello,
I am trying to configure Callcentric on Asterisk 13, Freepbx 14 to allow me to transfer an answered inbound call to a cell phone/landline and pass the Original callers Caller Id to the outbound call. I have been working with Callcentric support and can’t seem to get anywhere with it. They claim this can be done and said the following…

“In order for the caller ID passthrough feature to work, there must be an inbound call “leg” that came from our servers, and on the outbound call “leg” MUST reference (via the In-Reply-To header) the call-ID of the inbound call “leg”.” Your PBX IS adding the In-Reply-To header when it does reach your PBX… The main issue is that your PBX is failing to send this header on the outbound “leg” of the call. Based on the logs that you have provided."

Can anyone tell me how to get the “In-Reply-To header” to pass on the outbound leg of the transfer as Callcentric said that is what is missing?

[litmount (Randy Risser)]

Solved! Added this to extensions_custom.conf file.

[from-pstn-toheader-inreplyto]
exten => s,1,Noop(Trying to add ${SIPCALLID} to the In-Reply-To Header)
exten => s,2,SIPAddHeader(In-Reply-To: ${SIPCALLID})
exten => s,3,GoTo(from-pstn-toheader,s,1)

[macro-dialout-trunk-predial-hook]
exten => s,1,SIPAddHeader(In-Reply-To: ${SIPCALLID})

The most import part that I was missing was the [macro-dialout-trunk-predial-hook].
Also, you have to make sure to set your trunk context to from-pstn-toheader-inreplyto for this to work.

Calls that are blind transfered to external number now show the original callers number on receivers device.

[dcorwin822 (United States)]

I have this code working, however I also am getting an empty “in-reply-to” being sent before the one with the correct information. Does anyone know where this empty header is coming from?