Fix HP Error 79: Service Error – Critical
critical Severity: critical
If your HP printer is displaying error 79, do not worry – this is a known issue with a proven fix. This error typically indicates service error – critical that can usually be resolved without a service call. Follow the steps below to clear this error.
What Causes HP Error 79?
This error can be triggered by one or more of the following issues:
- Invalid print job data crashing the printer firmware
- Incompatible or corrupted firmware
- Network protocol error during print job transmission
- Third-party solutions or embedded apps causing conflicts
How to Fix HP Error 79
Follow these steps in order. After each step, check whether the error has cleared before proceeding to the next one.
- Step 1: Turn off the printer, wait 30 seconds, and turn it back on
- Step 2: Disconnect the network cable before powering on to prevent the bad job from being resent
- Step 3: Clear all queued print jobs on the computer and print server
- Step 4: Update the printer firmware to the latest version
- Step 5: If the error occurs with specific files, try converting them to PDF before printing
- Step 6: Reset the printer to factory defaults if the error persists after firmware update
Affected HP Printer Models
The following HP printer models are known to display error 79:
- HP LaserJet Enterprise M607dn
- HP LaserJet Enterprise MFP M635h
- HP LaserJet Pro M404dn
- HP LaserJet Pro M428fdw
Related HP Error Codes
If you are troubleshooting error 79, these related error codes may also be relevant:
- 49.4C02 – Critical Firmware Error
- 50.2 – Fuser Warm-Up Error
- 13.A3 – Paper Jam in Tray 2/3 Area
- 59.F0 – Motor Error
- 0x6100004a – Carriage Jam Error
Frequently Asked Questions
What is HP error 79?
Error 79 is a critical firmware crash on HP LaserJet printers, similar to a computer blue screen. The printer’s processor encountered data it cannot handle, causing a system halt. It is almost always caused by a problematic print job or firmware issue.
How do I prevent error 79 from recurring?
Update the firmware, ensure you are using the latest HP print driver, and avoid printing extremely complex or corrupted files. If the error happens on a network printer, check for problematic jobs being sent from specific computers.
Error still not resolved?
If the steps above did not fix the error, the issue may require professional service. Contact the manufacturer support line or visit an authorized service center near you.