This function can only be used by the first two extensions in the system. A button set to this function allows the user to unlock any extension without needing to know the code that was used to lock that extension. When the button is pressed, the user is prompted to enter the number of the locked extension.

If an extension already has a button set to this function, creating another button with this function will automatically clear the setting from the existing button.

To access this function without a programmable button:

On DS and ETR phones, press FEATURE and then dial 22.

On BST phones, press FEATURE and dial 937.