Im not using a PBX system I simply plug all units into my network switch and configure each phone with the SIP details provided by BT. I can manage my lines online with BT through an online portal where I have created a call pick up group however it still does not work. BT have advised me because it is not one of their devices they cannot offer support which is not very helpful. I wasn't too sure if each device could be configured through its IP address? As you can see I do not have a great deal of knowledge in this, but any help is much appreciated.
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