I was called to assist with an incident ticket whereby a Polycom SoundStation IP 6000 conference phone was not able to make or receive calls.
The first thing I did was to check what was the error message when trying to call the phone. The error displayed was “go off hook” and initial impression was that the phone was plugged out but based on the error this could not be the case.
When I check the phone screen, it was showing that the phone was being forwarded to an extension that did not exist hence the error. A little background knowledge, this phone is connected to an Alcatel VoIP Telephony system using the sip protocol. The way this system works is that is an extension does not exist in the system, it immediately give a message “go off hook” so it was strange when I got this message when testing the issue.
So the solution as you probably conclude is to disable the forwarding (which should not even be on a conference phone).
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