There are two ways.
1) In the IP Set Assignment form, you can enter in the MAC address of the set. You find the MAC on the bottom of the set. The format is:
XX:XX:XX:XX:XX:XX
2) In the System Options Assignment form you will see an entry of "IP SET REGISTRATION". Beside that entry, there should be something like *** (Mitel Default) or whatever. Doesn't matter what it is, you can change it to *123 if you want. The Set should be prompting you on the display to enter PIN. The PIN = IP SET REGISTRATION CODE + extension number. Depending on the set, you press either the hold button or the blue superkey button. The PIN will then register the set MAC to the extension. You only have to do this once.
good luck!
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