How can I fix my Samsung SF5100 fax?

Some fax machines are capable of making the distinction between FAX and VOICE calls. :)

First, can you make a copy on this machine?

If you can, then we know the memory is not full, and there is plenty paper and toner. The machine works for sure.

Second, get somebody to send you a fax MANUALLY, that is they should dial your fax number as if making a regular phone call from their fax machine.
When your fax rings, pick up the receiver and ask the other party to press their 'Start' button.
As soon as they do, you will hear their fax 'chirping'.

When you hear this 'chirping' press the 'Start' button on your fax machine.

It should work unless there is a problem with the phone board inside your fax.

I suspect the most likely cause is that the 'Ring Pattern' is not set correctly.
It should be 'Normal' or 'Standard'.

In days of yore, the telephone company would allow up to 4 different numbers using a single line, and each number had a "distinctive ring pattern".
In theory, one could set the fax machine to react to a specific ring pattern only.

I trust you have the User's Manual handy. :)

faxmando@yahoo.com
December 2008