HP Officejet Pro 7740 error 12345

[TruongDoan99]

Hi friend,

My HP OfficeJet 7740 printer shows a green screen with error code 12345 after a power outage occurred during a firmware update.

Could you please provide the .rfu firmware file or any instructions to help me fix this issue?

Thank you,

[Max3Aj]

@TruongDoan99, Welcome to HP Support Community. 

Thank you for posting your query, I will be glad to help you. 

I understand you're facing a green screen with error code 12345 on your HP OfficeJet Pro 7740 after a power outage during a firmware update. This situation typically indicates a corrupted firmware.

Please follow these steps, 
 

Download the firmware update utility:

• Go to the official HP page: https://support.hp.com
• Search for HP OfficeJet Pro 7740 firmware.
• Download the latest firmware .exe or .zip version for your OS.

Put the printer in recovery/bootloader mode:

• If the printer is stuck on the green screen, disconnect power.
• While holding down the Power button, plug the printer back in and continue holding for 10–15 seconds.
• If successful, the printer may enter a special recovery mode (blank or solid color screen).

Connect via USB cable (not Wi-Fi):

• Plug the printer directly into your PC using a USB cable.
• Make sure it appears in Device Manager as a printer or USB Device.

Send the .rfu file:

• If you extracted a .rfu file from the downloaded firmware package, open Command Prompt as admin.
• Use the command:

copy /b firmwarefilename.rfu \\<printername>\USB001

Or use the full path to the USB port detected.

• Alternatively, if the firmware updater tool is an executable (.exe), run it and it may detect the printer in recovery mode and flash the firmware.

If the Printer Is Not Detected

• Try a different USB port or cable.
• Ensure no HP Smart or background print services are blocking communication.
• Try updating from a Windows PC, not macOS or mobile.

I hope this helps. 

Take care and have a good day. 

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Select "Yes" on the bottom left to say “Thanks” for helping! 

Max3Aj

HP Support