You can find the menu on the printer's control panel below.
On the Web Config screen, you can find the menu below.
Fax tab > Basic Settings
If a password entry screen is displayed, enter the password.
Select the fax transmission speed. We recommend selecting Slow(9,600bps) when a communication error occurs frequently, when sending/receiving a fax to/from abroad, or when you are using an IP (VoIP) phone service.
Automatically corrects errors in the fax transmission (Error Correction Mode), mostly caused by telephone line noise. If this is disabled, you cannot send or receive documents in color.
Detects a dial tone before starting to dial. If the printer is connected to a PBX (Private Branch Exchange) or digital phone line, the printer may fail to start dialing. In this situation, change the Line Type setting to PBX. If this does not work, disable this feature. However, disabling this feature may drop the first digit of a fax number and send the fax to the wrong number.
Select the type of phone system to which you have connected the printer. When set to Pulse, you can temporarily switch the dialing mode from pulse to tone by pressing 
("T" is entered) while entering numbers on the fax top screen. This setting may not be displayed depending on your region or country.
Select the line type to which you have connected the printer.
When using the printer in an environment that uses extensions and requires an external access code, such as 0 and 9, to get an outside line, select PBX. For an environment that uses a DSL modem or terminal adapter, setting to PBX is also recommended.
Select Use, and then register an external access code such as 0 or 9. Then, when sending a fax to an outside fax number, enter # (hash) instead of the real code. # (hash) must also be used in Contacts as an external access code. If an external access code such as 0 or 9 is set in a contact, you cannot send faxes to the contact. In this case, set Access Code to Do Not Use, otherwise you must change the code in Contacts to #.
Enter your sender name and fax number. These appear as a header on outgoing faxes.
Your Phone Number: You can enter up to 20 characters using 0-9 + or space. For Web Config, you can enter up to 30 characters.
Fax Header: You can register up to 21 sender names as necessary. You can enter up to 40 characters for each sender name. For Web Config, enter the header in Unicode (UTF-8).
If you have subscribed to a distinctive ring service from your telephone company, select the ring pattern to be used for incoming faxes. The distinctive ring service, offered by many telephone companies (the service name differs by company), allows you to have several phone numbers on one phone line. Each number is assigned different ring pattern. You can use one number for voice calls and another for fax calls. Depending on the region, this option may be On or Off.
Select the number of rings that must occur before the printer automatically receives a fax.
When you answer an incoming fax call on a phone connected to the printer, you can start receiving the fax by entering the code using the phone.
Set the start code of Remote Receive. Enter two characters using 0-9, *, #.
Select options to reject receiving junk faxes.
Rejection Number List: If the other party's phone number is in the rejection number list, set whether to reject the incoming faxes.
Fax Header Blank: If the other party's phone number is blocked, set whether to reject receiving the faxes.
Unregistered Contacts: If the other party's phone number is not in the contacts, set whether to reject receiving the faxes.
You can register up to 30 fax numbers to reject the faxes and calls. Enter up to 20 characters using 0-9, *, #, or space.