Plug the serial port Feature Key dongle into the serial port on the IP Office control unit (IP Office Small Office Edition, IP406 V2 and IP412 control units).
Start Manager and click to load the IP Office system's configuration.
Double-click on System in the left-hand panel.
On the System tab, the License Server IP Address field is used to set the location of the feature key.
For a serial port license key, set the License Server IP Address to be blank.
Click on License in the left-hand panel. Any existing license should appear in the right-hand panel.
To add a license, double-click on the right-hand panel. Enter the new license into the menu that appears and click OK.
The Status of the new license should show Unknown and name the license as expected. If its Status is Unknown and name Invalid, the most likely cause is incorrect entry of the license key characters.
Click on to send the configuration back to the IP Office. The menu that appears will indicate whether a reboot is required.