You can send faxes to the confidential boxes or the relay boxes in the recipient's fax machine when the recipient's fax machine has the feature to receive confidential faxes or relay faxes. The recipients can receive them securely, or can forward them to specified fax destinations.
Place the originals.
Select Fax on the home screen.
Select the contacts list and select a recipient with a registered subaddress and password.
The following icon displays the contacts list.
You can also select the recipient from 
(Recent) if it was sent with a subaddress and password.
Select the Fax Settings tab, and then make settings such as the resolution and the sending method as necessary.
Send the fax.