My fax comes on when its not plugged in - HP Officejet J5780 All-In-One Printer

The "line" port is for the telephone line you intend to use for faxing.
The "Tel" port is for an external telephone to be plugged in.
The "Handset" port is for the hanset which may or may not have come with the fax machine.

My first assumption would be, since this appears to be a new fax machine for you, to ensure that the telephone line is plugged into the correct port on the fax machine. There are usually two ports, a telephone port and a line port, you want the telephone line to be plugged into the "line" port.

Let me know.

-David.

You configure you fax program.Such as line type,fax number,or you follow user manual,how can use it?
It is problem setup or configure not problem machine.

plug your single line phone into the phone outlet on your fax the plug line from your wall inot line spot on the back of the fax. set your fax to manual answrer. you will then need to push start when a fax comes in to receive it.

You do not need 2 lines for a fax/phone. The only trouble is that you will not be able to tell the differance between a phone call and a fax unless your called first. There is a feature call distinctive ringing that should be offered through your phone company. The different types of ring would indicate a phone call or fax. The answer to the 'splitter' is that if you plug in your fax machine directly into the jack, most newer fax have a 2nd plug in the back labeled 'ext', this is where you can plug in a phone for the same number.

You need to purchase a cross-over cable to use on your fax machine. This cable will change line 2 to line 1 for the fax so it will pick up the line when line 2 rings and not line 1.

If you want to use a regular cable you'll have to have someone rewire the jack in the wall to swap line 1 and line 2, then just plug the fax machine into this jack.

You have the phone line from your wall plugged into the headset and not into the machine.

try unplug the phone line and use another phone to call again, then c if it has a fax tone, if it does, there might be another fax machine that picks up the fax before the Dp-190 pick up the fax.

another thing you can try is to change a new phone line that connect between ur machine and the plug.

Just a suggestion. This effect can happen if you have plugged the line cord into the tel jack instead of line jack.

You should be able to send and recieve faxs in the sleep mode. You need to reset the machine, pull out the plug, hold down the menue key while you plug the machine in. When maintanence comes up in the display enter 01 and wait. Whwn maintanence comes up again press 99. DO NOT PRESS ANY OTHER NUMBERS OR YOU WILL DAMAGE THE MACHINE BEYOND REPAIR. Your fax is now reset and completley empty, you will have to put in your name etc and sleep mode will be set to "0" minutes