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Click "Add Device" below
Now, set the tftp server on the phone to: "s[server_id].trixbox.fonality.com"
Reboot your phone
Now click on Extensions in your Admin Panel and select the proper extension for this phone (if you haven't created the extension yet, please read How do I add an extension?)
Select your newly created device from the list - devices that are already paired with an extension will display the extension in ( ) as pictured:
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