BT Business VOIP and 3CX

[worcester1]

Hi All

I am having some real issues with a BT Business VOIP account in the UK. (with an 05 number?)

BT in the documentation say it is modified SIP and should work on any phone system.

Even though the trunk is registered i can not make an incoming or outgoing call on the trunk at all.
Has anybody in the forums got 3cx to work with BT VOIP?

In the past when i have had a trunk register and i cant call from it i have had to change the outgoing CLI to start 441210004444 instead of 01210004444. When i take the 0 away from the BT 056 number the trunk fails to register at all.

I'm using 3CX V12 on Win7 Pro

Domain: bmnhb-03.bt.com
Alt Domain: sip.bbvservice.nat.bt.com

Any help would be much appreciated as Bt just don't want to know and only support trunks on BT kit. (standard)

Thanks
Richard

 

[leejor]

If the trunk shows registered, what does the 3CX log show when you receive a call? Why does it fail?

Has BT explained (or is there any documentation) on what digit format/length they are expecting on outbound calls?

 

[worcester1]

HI,

The log says Leg L:61.3[Line:10003>>07891XXXXXX] is terminated: Cause: 480 Temporarily Unavailable/INVITE from 62.239.15.136:5060

I've just spoken to BT and they could not of been more unhelpful.
Any thoughts as to what this error means?

Thanks
Richard

 

[leejor]

Do you get the same error when calling other numbers? It might be that there is an issue with the mobile number you are calling, or the digits you are sending.

Doing some searches comes across a few others having the same issue with BT, but few solutions.

http://forum.snomone.com/index.php/topic/6335-trunk-configuration-for-british-telecom-voip-lines/