My All in one has crashed - is it curtains?

[VideoPete]

HI

I'm having problems with my HP 32 inch all in one

When I turn on I get the message in red

Secure Boot Violation Invalid signature detected check secure boot policy in setup

Then in blue I had boot device not found Hard Disk (3F0) but it wont let me access F2 system diagnostics now

I did get into F2 once and all checks ran ok

I've also had CMOS reset (502)

It is out of warranty

It is hot today in the UK so I'll let it cool down this evening and have another go

Anyone with similar experience?

Any advice appreciated

[Hawks_Eye]

Hi @VideoPete 

Welcome to the HP Support Community! We're here to help you get back up and running.

Thank you for sharing the details regarding your HP 32‑inch All‑in‑One computer. Based on the messages you described — Secure Boot Violation, Boot Device Not Found (3F0), and CMOS Reset (502) — the system is indicating issues with both firmware configuration and the hard drive boot process. Since diagnostics did run successfully once, the hardware itself may still be intact, and there are structured steps you can follow to restore operation.

Access BIOS Setup

• Power on the computer and immediately press F10 repeatedly until the BIOS Setup screen opens.
• If the system does not respond, allow it to cool down and try again.

Restore Secure Boot Keys

• In BIOS, go to Security > Secure Boot Configuration.
• Select Restore Factory Keys.
• Save changes and exit BIOS.
• Restart the computer to check if the Secure Boot Violation clears.

Verify Boot Mode and Hard Drive Detection

• In BIOS, confirm that the hard drive is listed under Storage.
• Ensure UEFI Boot Mode is selected.
• If the drive is not detected, reseating the drive or checking connections may be required.

Run HP Diagnostics Again

• Press F2 immediately at startup to access HP PC Hardware Diagnostics.
• Run the System Test and Hard Drive Test.
• If the tests pass, the issue is likely firmware or boot configuration rather than hardware failure.

Update BIOS

• Use another computer to download the latest BIOS update for your model from HP’s official support page:
  HP PCs – Updating the BIOS (Basic Input Output System)
• Create a BIOS update USB and apply it to your All‑in‑One.

CMOS Reset (502)

• This message indicates the BIOS settings were reset. After updating or restoring, re‑enter BIOS and confirm date, time, and boot settings are correct.

System Recovery

• If the hard drive is detected but the boot device not found error persists, use HP Cloud Recovery Tool to create recovery media and reinstall the operating system.

By following these steps, you can systematically address the Secure Boot and boot device errors. Cooling the system before retrying is a good idea, but the structured BIOS and recovery steps are key to restoring functionality.

Take care, and have an amazing day!

Regards, 

Hawks_Eye