hp 9730 printer prints solid black lines overlay text

[StirlingLass]

New hp 9730 printer (bought months ago, used only a few times when it stopped working... likely a firmware update issue).  Has new HP genuine cartridges.  Printer prints solid black lines that overlay the text whether printing a Word doc or even just a notepad .txt file (no hidden format or control characters).  

Tried typical unplug, hold power button, wait, remove cartridges, then replug in, turn on/connect, insert cartridges.  Checked firmware/drivers -- according to HP support tools online and on my PC, the firmware/drivers are up to date. Recent firmware update July 8 2026 (today is July 14, first time to print since update and it's all black lines.  

This "doorstop" can print out the print-head alignment and test pages without the lines, but anything else printed, like txt file, is overlayed with thick black lines.

[VikramTheGreat]

Hi @StirlingLass,

Welcome to the HP Support Community.
 

Thank you for providing the detailed description and the sample printouts. The photos are very helpful. From what you've shared, the printer's internal printhead alignment and test pages print correctly, while documents printed from applications such as Notepad and Microsoft Word are overlaid with thick horizontal black bars. Since the internal reports print normally, the printhead and HP genuine cartridges are likely functioning correctly, which points more toward a print processing, driver, or print settings issue rather than a hardware failure.
 

To help us narrow this down, could you please let us know:

• Are you printing from Windows 10 or Windows 11?
• Does this occur from all applications (Word, Notepad, PDF readers, web browsers), or only specific ones?
• Is the printer connected via Wi-Fi, Ethernet, or USB?
• Have you tried printing the same document from another computer or mobile device, and if so, does the issue occur there as well?
   

In the meantime, please try the following recommended steps:

Check the print settings

Incorrect print preferences can sometimes cause unexpected print output.

• Open the document you want to print.
• Select File > Print, then choose your HP OfficeJet Pro 9730.
• Open Printer Properties or Preferences.
• Verify that the Paper Size and Paper Type match the paper loaded in the printer.
• Set Print Quality to Normal.
• Disable any special print options, such as Print in Grayscale, Black Ink Only, or other advanced print enhancements if they are enabled.
   

Print from a different application

This helps determine whether the issue is application-specific or affects all print jobs.

• Print a PDF document.
• Print a JPEG or PNG image.
• Print a Windows Test Page.
   

Reinstall the printer driver

Since the issue appeared after a recent firmware update and the internal reports print correctly, reinstalling the printer software can refresh the Windows print driver and print pipeline.

• Remove the printer from Settings > Bluetooth & devices > Printers & scanners.
• Restart the computer.
• Install the latest printer software using the HP App or the HP Support website.
• Add the printer again and test printing from Notepad.
   

Compare with internal printer reports

Continue comparing the printer's internal reports with computer-generated documents.

• If the internal reports remain clean while documents continue to show black horizontal bars, it indicates the printer hardware is functioning correctly and helps isolate the issue to the print driver, print settings, or the print data being sent from the computer.
   

Next Steps

Once you've completed the steps above, please let us know:

• Does a Windows Test Page print with the same black horizontal bars?
• Do PDFs or image files print correctly?
• Does the issue occur when printing from another computer or mobile device?
• Does reinstalling the printer driver change the behavior?

The answers to these questions will help determine whether the issue is related to the Windows print driver, print settings, or how the print job is being processed, allowing us to provide the most appropriate next steps.
 

We look forward to your update.
 

Take care and have a great day!

[VikramTheGreat]

Hi @StirlingLass,
 

We look forward to your update.
 

Take care and have a great day!

[StirlingLass]

After further QA testing, I've narrowed down the reproducible steps.  In short, on the 9730, printing from my Win 10 PC, if I select B/W and Draft (to save ink), the lines appear.  If I print at better or best quality, the lines do not appear.  (per your questions, all the printer settings including paper size etc are correct).

At first blush, this issue looks like HP wanting me to use alot more ink (increase their ink sales), but I am sure it is not that nefarious, and instead is a bug in the printer firmware. This does not happen on our prior printer - the OfficeJet pro 7740.  When might you anticipate a software update to the field to repair this issue... I like to print in draft mode nearly 100% of the time.

Thank you