Printer is printing small triangles by itself

[jepsenkc]

My HP OfficeJet Pro 8710 is printing all by itself. I have not set it up as a fax machine, or set up the mobile, or online printing which was possible during installation a few years ago. I will come home, and the printer will have print multiple pages with a small black triangle in the corner. This has happened when I was sitting next to the printer too, and I will cancel the job because it will keep printing these pages until the printer runs out of paper. No one is printing this or sending jobs to the printer when this happens. I am guessing that someone is trying to print to it from an outside network or something because this has happened when no one in the house is even on a computer. I also want to mention that when I look up the print queue on the computer hooked up to the printer, there is nothing there even though the printer is just sitting here saying it has run out of paper. I feel like usually I would expect to see the print job in the queue on the computer even if the printer ran out of paper, but there is nothing there. This is an intermittent issue that has happened about 4-5 times in the past month. Please help me stop this because it is now starting to cost me extra money in paper. 

[Kumar0307]

@jepsenkc, Welcome to the HP Support Community!

What does the printer print? Kindly attach an image of the same in your next post.

Is your printer connected to a wireless network or using a cable?

For now, let us try these steps: 

Reset the printer

1. With the printer turned on, disconnect the power cord from the rear of the printer.
2. Wait at least 60 seconds.
3. Reconnect the power cord to the rear of the printer.
4. Turn ON the printer, if it does not automatically turn on.
5. Wait until the printer is idle and silent before you proceed.

Note: HP recommends connecting the printer directly to a wall outlet rather than a surge protector or a power strip.

Update the printer firmware

Click here to download and install the latest firmware from your computer.

Click here to know different methods of updating printer firmware.

Remove web services.

1. On your printer control panel, touch or press the HP ePrint icon or button, and then touch or press Settings.

   If your printer control panel does not have an icon or button, navigate to Web Services Setup, Network Setup, or Wireless Settings to open the Web Services menu, depending on your printer model.

2. Select Turn Off, Disable, or Remove, depending on your printer model.

3. Follow the on-screen instructions to turn off Web Services.

Monitor the printer.

Let me know how this goes.

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