HP LaserJet Error 79

How to Fix HP LaserJet Error 79 Service Error

If your HP LaserJet printer suddenly displays a “79 Service Error” message and starts rebooting endlessly, you’re not alone—this is a frustrating but common issue that affects many models, like the Pro MFP M283fdw, M426, or even older ones like the CP2025. It often points to a communication glitch, a corrupted print job, outdated firmware, or network overload, causing the printer to crash mid-task. The good news? Most cases can be resolved at home without calling in a tech. In this guide, I’ll walk you through straightforward, step-by-step fixes based on proven solutions from HP support and real-user experiences. Let’s get your printer back online.

Step 1: Perform a Basic Power Cycle and Cable Check

Start simple—many errors stem from temporary glitches or loose connections.

  • Turn off the printer: Press the power button and wait for it to fully shut down (the lights should go off).
  • Unplug everything: Disconnect the power cord from the wall (not just the printer), Ethernet cable (if connected), and any USB cables. If you’re using a surge protector or extension cord, plug directly into a wall outlet to rule out power inconsistencies.
  • Wait 60 seconds: This clears residual power and resets the internal memory.
  • Reconnect and power on: Plug in the power cord first, wait 30 seconds, then reconnect cables. Turn on the printer and try a test print from your computer.

This alone resolves about 40% of cases, especially if a recent power flicker triggered it. If the error persists, move on.

Step 2: Clear the Print Queue on Your Computer

A stuck or oversized print job is a top culprit for HP LaserJet Error 79 —it overwhelms the printer’s processor.

  • On Windows:
  1. Open the Start menu, type “Services,” and hit Enter.
  2. Find “Print Spooler” in the list, right-click it, and select “Stop.”
  3. Open File Explorer and navigate to C:\Windows\System32\spool\PRINTERS.
  4. Delete all files in this folder (don’t worry, it won’t harm your system).
  5. Back in Services, right-click “Print Spooler” and select “Start.”
  • On macOS:
  1. Go to System Preferences > Printers & Scanners.
  2. Select your HP printer and click “Open Print Queue.”
  3. Click the “X” to cancel all jobs, then restart your Mac.

Test printing a simple page, like a Notepad document. Users report this fixes boot loops caused by corrupted jobs.

Step 3: Update or Downgrade the Printer Firmware

Firmware bugs, especially after automatic updates, are notorious for triggering Error 79. HP has released patches, but sometimes rolling back helps.

  • Check your current firmware:
  1. On the printer’s control panel, go to Settings > Reports > Print Configuration Page (or similar, depending on model).
  2. Note the firmware version listed.
  • Download the latest from HP:
  1. Visit HP’s support site and enter your printer model (e.g., “LaserJet Pro M283fdw”).
  2. Go to Software and Drivers > Firmware.
  3. Download the newest version for your OS.
  • Install it safely:
  • Disconnect from networks (unplug Ethernet/Wi-Fi) to avoid interruptions.
  • Use a USB connection if possible for direct transfer.
  • Follow on-screen prompts—do not turn off the printer during the update (it takes 5-10 minutes).

If the error started after an auto-update, try downgrading to a previous stable version from HP’s archives. This has saved printers from endless reboots.

Step 4: Reset the Printer’s NVRAM or Perform a Full Factory Reset

When memory glitches build up, a deeper reset clears them out.

  • NVRAM Init (safer first step):
  1. Turn off the printer.
  2. Hold down the “OK” or “Wireless” button (check your model’s manual for the exact one).
  3. Turn it back on while holding the button until the lights flash or a message appears.
  4. Release and wait for it to restart. This resets network settings without wiping everything.
  • Full Factory Reset (if NVRAM fails):
  1. Access the control panel: Settings > Service > Restore Defaults (or similar path).
  2. Select “Factory Reset” and confirm. Note: This erases custom settings, so reconfigure Wi-Fi afterward.

Reconnect to your network and test. This step often breaks the reboot cycle.

Step 5: Troubleshoot Network and Hardware Issues

If your printer is on a shared network, traffic overload (like from discovery protocols) can cause crashes.

  • Isolate the connection: Print via USB only to test—bypass Wi-Fi/Ethernet. If it works, the issue is network-related.
  • Disable WS-Discovery: On Windows, open Services, find “SSDP Discovery” and “UPnP Device Host,” and stop them temporarily. Restart and test.
  • Check for hardware faults: Inspect for loose internal cables or faulty DIMM memory modules (if your model has them—rare for consumer printers). If you suspect the formatter board (main logic board), it might need professional replacement.

When to Seek Professional Help

HP LaserJet Error 79, If these steps don’t resolve it, the problem could be a failing power supply or formatter—common in older units. Contact HP Printer Support via their website (provide your model and serial number) for warranty checks or remote diagnostics. For out-of-warranty fixes, a local tech might cost $100-200, but it’s cheaper than a new printer.