Fax won't send or keeps failing

Unplug the printer's phone cord from the wall and plug in an ordinary corded phone. If you hear no dial tone, the problem is the wall jack or the phone service rather than the printer; try another jack, or report the fault to your phone provider through its website or account.

The cord from the wall jack must go into the printer's port marked LINE or shown with a wall-jack symbol. The other port, often marked EXT or TEL, is only for an extension phone or answering machine. Use the cord that came with the printer if you have it, and avoid long cords and splitters while testing.

Many printers have a fax test or line check in the fax setup, tools or reports menu. It checks the cord, the port and the dial tone, and prints a report that says what failed.

If you have DSL internet on the same phone line, plug a DSL filter into the wall jack and connect the printer to the filter's phone socket. Without one, the internet signal interferes with fax tones.

If your office dials 9 or another code for an outside line, add it before the number or set it as the dialing prefix in the fax settings. Add a pause after it, usually with a pause or redial button or a comma, so the phone system has time to connect. Include the country or area code for long-distance faxes.

Enter your name, fax number, date and time in the fax setup menu. Some printers won't send until these are set, and in some countries, including the US, faxes are legally required to identify the sender.

In the advanced fax settings, set the fax or modem speed to a lower value such as 14400 or 9600 bps, sometimes labelled medium or slow. Make sure error correction mode (ECM) is on, as it resends damaged parts of a page on noisy lines.

Dial the fax number from an ordinary phone; you should hear fax tones, not a person or voicemail. Then send a one-page fax to a different fax number you know works. If that goes through, the problem is at the original recipient, such as a busy line, no paper or a full memory.

Print the fax log or transmission report from the reports menu. It lists each attempt with a result or error code, and your manual or the maker's official support site explains what the codes mean for your model.