Make the following settings when using the printer in offices that use extensions and require external access codes, such as 0 and 9, to get an outside line.
Select Settings on the printer's control panel.
To select an item, use the 
buttons, and then press the OK button.
Select General Settings > Fax Settings > Basic Settings.
Select Line Type, and then select PBX.
When sending a fax to an outside fax number using # (hash) instead of the actual external access code, select the Access Code box to make this to Use.
The #, entered instead of the actual access code, is replaced with the stored access code when dialing. Using # helps avoid connection problems when connecting to an outside line.
You cannot send faxes to recipients in Contacts that have external access codes such as 0 and 9.
If you have registered recipients in Contacts using an external access code such as 0 and 9, set the Access Code to Do Not Use. Otherwise, you must change the code to # in Contacts.
Select the Access Code input box, enter the external access code used for your phone system, and then select OK.
The access code is stored in the printer.