Cannot send or receive a fax

Last Update: August 9th, 2021

Help! My fax machine (or computer with fax software) can is having trouble sending and receiving faxes – what do I do?

A setting on the fax machine has changed

Common settings that may have been changed: Automatic answering being turned off, or the number of rings to answer has changed.

Explanation: Changes to a fax machine’s settings can cause the fax to no longer send or receive.

Symptoms: Settings have been changed without changing them back. Also, the fax was working before, and nothing else has changed.

Resolution: Turn the settings back to where they were.

The telephone line has been changed to a VoIP (Voice over IP) telephone line, or the telephone company has upgraded the line infrastructure to VoIP.

VoIP and fax are mostly incompatible. Even when a test page completes, a fax machine on a VoIP phone line will often fail with multiple pages or more complex documents.

Explanation: VoIP modifies (compresses) a phone signal to enable the call to transmit over the internet. This compression makes the fax signal unable to be understood by the receiving fax machine.

Many VoIP phone lines are not compatible with fax, even if they advertise they are.

Symptoms: Sometimes faxes g0 through, sometimes they do not (sometimes they never go through). Faxes that are many pages or include graphics are more likely to fail. There are some fax numbers that a fax is always impossible to communicate with.

Resolution: Work with the phone provider to enable faxing on the line, or consider an alternative.

Voicemail, an answering machine, modem, or other device has been added onto the telephone line and is answering before the fax machine can answer.

Another device on the same phone line can cause a receiving fax to fail if it answers the phone line before the fax.

Explanation: If another device answers before the fax machine does, the fax machine will not answer phone line to receive the fax.

Resolution #1: Get rid of the extra device on the phone line.

Resolution #2: Add another phone line for the extra device. When each device has its own phone line, it can operate independently and not interrupt the other device

Resolution #3: Add an extra phone number to the same phone line and use a fax with dual ring detection (DRPD). When the second phone number rings (with a unique ring) the fax machine will answer (but not the answering machine, voicemail, or modem).

Resolution #4 (won’t work for voicemail): Add a TAM device, or use a fax machine with TAM. The TAM will answer the phone line when it rings, and route the call to the appropriate device.

A telephone line service such as call waiting, billing tone, privacy block, security screen, anonymous call rejection, or privacy manager has been added.

Line services can interrupt a fax’s communication. They should not be present on a fax line.

Explanation: Extra line features (such as call waiting and billing tones) can make beeps on the line. Security screens and anonymous call rejection can prevent calls from connecting as fax machines cannot navigate their menus or understand their errors.

Symptoms: The transmissions frequently end part of the way through (call waiting, billing tone). The fax can send but not receive (privacy block, security screen, anonymous call rejection, privacy manager).

Resolution: Disable the extra phone features and try the fax again.

More resources

Manufacturer Support

Telecom support

Further troubleshooting

Cnet forums(Samsung) – Cannot receive faxes from one number