If your having Secure Boot Issues / Boot Loop when Enabling Secure Boot / Black Screen when Enabling Secure Boot
after trying everything including the BIOS update I still had the boot loop / black screen issue followed by
INVALID SIGNATURE DETECTED CHECK BOOT POLICY IN SETUP
- Reset Your BIOS to factory / Reset Keys to Factory, if this works for you, great if not try Manual Key Enrolment no one is talking about it for some reason and its so simple, I hope it saves you all the hours I used trying to figure this issue out for Black Ops 7 / Warzone / Battlefield 6!
My Device:
SER6Max 6900
- Most recent BIOS, [✔]
(not required for method)
- TPM2.0 [Enabled] [✔]
(check yours is enabled in BIOS)
- Secure Boot [Active] - Boot Loop/Black Screen Issue [FIXED][✔]
I believe this FIX will work on other SER models and maybe possible without the BIOS update.
Manual Key Enrolment:
Beginner Friendly*
To Enter the BIOS
Restart your PC.
Tap the Delete key repeatedly until a grey/blue menu appears. (This is the BIOS).
Use your arrow keys to go to the Security tab.
Select Secure Boot and press Enter.
Ensure Secure Boot is set to Enabled.
Change the ‘Standard’ option to ‘Custom’
Locate Key Management and press Enter.
Select Enroll EFI Image (or sometimes called Authorized Signature).
A file browser will appear. You need to “drill down” through these folders:
Select your hard drive (usually labelled FS0:). (it might just open your hard drive automatically)
Open the EFI folder.
Open the Microsoft folder.
Open the Boot folder.
Find the file named bootmgfw.efi and press Enter.
The BIOS will ask if you want to enroll/trust this image. Select Yes.
Save and Exit
Press F4 (or F10, check the legend on the right of your screen) to Save & Exit.
Your PC will restart, and Windows should now boot perfectly with Secure Boot [active].
Why does this work?
Normally, the BIOS uses “Factory Keys” to trust Windows. Sometimes, a Windows update or a BIOS setting change breaks that trust.
By manually selecting bootmgfw.efi, you are effectively giving the BIOS a “digital fingerprint” of your specific Windows installation and saying, “This one is allowed.”
