When you try to ring the ddi it hangs up internally and if you call externally it forwards onto our customer service number.
A quick overview this is part of our corporate wan so all ports are open,PABX is an Alcatel 4760. The 580 has the latest firmware.
EDIT: We have installed the x-lite softphone app in which we can receive both incoming and outgoing calls.
This makes me believe it is a configuration issue on the 580IP