When experiencing issues with a a Polycom phone failing to register, in order to resolve the problem quicker, these best practices should be followed before escalating the problem to support:
Focus on the error message the phone shows on it's LCD, and act accordingly.
If the message indicates the problem may be in-house. e.g. the error message says "error DHCP failed", the problem is most likely network connectivity related: bad/unplugged network cable, switch/router problem (or another kind of interconnecting device, i.e. Power-line adapter), check all of the above, and reset the phone before escalating further.Sadly, Polycom doesn't have an exhaustive, or concise index/overview of error messages their phones can display on the LCD, and supposedly there aren't many error messages the phone can display. Hence, a quick-and-dirty reference of error messages follows:
"DHCP Error", or similarThe messages is pretty self-explanatory
"Missing files, config reverted", or similarThis message displays when there are errors in the configuration and a failure to download the configuration files force the phone to revert to its previous (known) condition with a complete set of configuration files.More info: FAQ-What-does-the-message-quot-Missing-files-config-reverted"Duplicate IP", or similarThe messages is pretty self-explanatory
"pre-3.3.0 params", or similarAbove simply tells the user that the phone has loaded certain configuration parameters or files that contain invalid/updated configuration parameters.More info: FAQ-What-is-the-meaning-of-the-Error-message-quot-pre-3-3-0
If none of the above fixes it, submit a support request with: a) the problem description, b) environment the phone is used in, c) Device's MAC address and line(s) configured/used on the device, d) Specify what was tried in order to resolve the problem, thus ruling out common culprits.What is meant by environment the phone is used in, is: Office vs. Home, VPN vs no VPN, networking device(s) the phone is connected to to reach the internet