If phone you want to re-configure a handset as internal after it has been setup as external handset, the the "boot server IP address" will not be correct for the phone to contact the Allworx server locally.

We recommendation you factory default the phone. 
1. (Config --> Set to factory Default). 
 Once you confirm it, the phone will reboot. 

If phone fails after reboot, you will need to add the Boot server IP and Contact serv IP into the phone. 

1a. (Config --> Network settings (password "allworx")--> Edit boot server (enter the local IP address of the Allworx). 

You also want to add that same address as the contact server 

2a. (Config --> Network settings (password "allworx") --> Edit Contact serv IP (enter the local IP address of the Allworx). 
3a. exit 
4a. exit 
5a. save to flash 
6a. reboot phone 
7a. When the phone reboots you will be prompted to add a new user. Select "Add" --> "Now" --> (select the user from the list)

​

remote phone, internal, external, setup new handset