Hi there, if the BitLocker Group Policy Configure TPM platform validation profile for native UEFI firmware configurations is enabled and PCR7 is selected by policy, it may result in the update failing to install. You can launch the Command Prompt to run certain command lines before you deploy the Secure Boot DBX on your Windows PC.
This security update makes improvements to Secure Boot DBX for the supported Windows versions listed in the "Applies to" section. Key changes include the following:
1. Windows devices that has Unified Extensible Firmware Interface (UEFI) based firmware can run with Secure Boot enabled. The Secure Boot Forbidden Signature Database (DBX) prevents UEFI modules from loading. This update adds modules to the DBX.
2. A security feature bypass vulnerability exists in secure boot. An attacker who successfully exploited the vulnerability might bypass secure boot and load untrusted software.
3. This security update addresses the vulnerability by adding the signatures of the known vulnerable UEFI modules to the DBX.
When you encounter frequent BitLocker recvoery key pop-ups, read the following solutions to deal with it:
Scenario 1: For the device doesn't have Credential Gard enabled
On a device that does not have Credential Gard enabled, run following command from an Administrator command prompt to suspend BitLocker for 1 restart cycle: Manage-bde –Protectors –Disable C: -RebootCount 1
Then, deploy the update and restart the device to resume the BitLocker protection.
Scenario 2: For the device has Credential Guard enabled
On a device that has Credential Guard enabled, run the following command from an Administrator command prompt to suspend BitLocker for 2 restart cycles:Manage-bde –Protectors –Disable C: -RebootCount 3
Then, you can deploy the update and restart the device to resume the BitLocker protection.
If you want to view the PCR7 binding status, just run the Microsoft System Information (Msinfo32.exe) tool with administrative permissions.