Printer, Fax

While attempting to continue printing from the Internet,
the printer displayed an error message "Phone Off-hook".
My printer has a phone line, not a hand held mouthpiece
that fits into a cradle. In other words, there is
no "hook". I have been baffled by this error message
before!

My printer is an HP OfficeJet G-85, a 3-In-One model,
that prints, faxes and scans. Usually I can print, but I
have not been able to send nor receive a fax. I input
the settings as prompted, but the machine will not fax.
Could there be a problem with the cable that connects the
printer to the phone jack outlet?

Please let me know how to eliminate these problems.