Using the Closed Network RX function
Closed Network RX is a function that restricts the peers by passwords. You can use this function only when the remote machine is one of our models that have the Password TX function.
In the administrator mode, select [Fax Settings] - [Function Setting] - [Closed Network RX], and select the [Password is changed.] check box (Default: [OFF] (not selected)). Then, enter the password to restrict communication peers (using up to four digits).
Inform the peer of the password you entered here.