The Secure Boot update failed. Unknown HResult Error code: 0x800700c1.

[movoodoo]

System Model: HP ProBook 450 15.6 inch G10 Notebook PC

OS Name: Microsoft Windows 11 Pro
OS Version: 10.0.26100 N/A Build 26100.6584 24H2

Original Install Date: 23.06.2025, 0:02:14

BIOS Version: HP V72 Ver. 01.10.00, 26.08.2025

After the operating system load, I receive the following message in Event Viewer (System):

"The Secure Boot update failed to update a Secure Boot variable with error Unknown HResult Error code: 0x800700c1. For more information, please see https://go.microsoft.com/fwlink/?linkid=2169931"

This message was immediately after installing the system.

Today i noticed, that a BIOS update is available:

https://support.hp.com/ua-uk/drivers/swdetails/hp-probook-450-15.6-inch-g10-notebook-pc/2101593792/s...

And this update has "Enables recent Windows cumulative updates to include the Windows UEFI CA 2023 certificate for platforms introduced in 2023 and earlier". 

After installing this update and rebooting, I still get this error message:

"The Secure Boot update failed to update a Secure Boot variable with error Unknown HResult Error code: 0x800700c1".

I tried:
1. Set default security settings in UEFI. (And all BIOS default settings).
2. Disable and enable Secure Boot.
3. Clear TPM.

How to fix this?

[resistencia]

Hi @movoodoo 

In windows search type CMD, in the result click run as administrator and type (One at a time and then enter)

sfc /scannow

DISM.exe /Online /Cleanup-image /Scanhealth
Dism.exe /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /RestoreHealth

then restart windows and check.

[movoodoo]

I forgot to write. Of course I did. And even completely reinstalled Windows. No result.

[movoodoo]

I forgot to write. Of course I did. And even completely reinstalled Windows. No result.

[resistencia]

Enter the BIOS and load the default settings. This error may be caused by Windows itself, but future updates may fix this problem. Are you having problems using your laptop?

If BitLocker is enabled, disable it and check for errors. Never update the BIOS with Bitlocker enabled. This is an important recommendation.

[movoodoo]

@Resistencia

I loaded BIOS default settings several times.

I don't have any problems with laptop.

I was looking at the event viewer for other reasons. And I saw this error message. It turns out that this is a fairly common error. There are also several similar issues in this community (with different laptop models).

I also figured that this error would be fixed in a future update. And I thought this update BIOS would fix the problem.

[resistencia]

I'm almost certain it's a Windows problem and not a laptop problem. Wait to update your Windows. Windows events are full of false positives.

[movoodoo]

@Resistencia

Thank you for your answer.

Bitlocker was on when I updated the BIOS. Then I turned it off and updated the BIOS again.

[movoodoo]

@Resistencia

Maybe you can tell me how I can find out if are updated new Certificate Authorities (Windows UEFI CA 2023) in UEFI?

[resistencia]

This is implemented by Windows and was already done in 2014. Go to Device Manager, click on Firmware, and check if the version there matches the BIOS version.

KB5036210: Deploying Windows UEFI CA 2023 certificate to Secure Boot Allowed Signature Database (DB)...