Hi, We are running 3CX v5.1.4510.0. Our provider is Engin in Australia. Our internal extensions all work fine and we can answer calls both extension to extension and via ring group. We have several tele-workers who work out of the office. We want them to be able to receive and make calls via 3CX. We have successfully set up an external extension that is a member of a ring group that can make calls and the extension rings when a call is directed to the group or called from another extension. The external extension cannot answer any incomming calls. The Server log indicates the extension is ringing as part of the ring group, but when the call is answered there is no indication in the log that the answer has been received by 3CX. I have tried a Thomson 2030, Grandstream GXP-2000 as well as the 3CX Softphone and none can answer the call. There is no firewall configured at the external site and as far as I can tell all the appropriate ports are open at the office end. Can anyone shed any light on why the server does not recognise that the call is being answered?