What does Windows error code 4435 (ERROR_SECUREBOOT_NOT_SUPPLEMENTAL_POLICY) mean?

ERROR_SECUREBOOT_NOT_SUPPLEMENTAL_POLICY

ERROR_SECUREBOOT_NOT_SUPPLEMENTAL_POLICY (LRESULT 0x00001153) This Win32 error means a base Secure Boot policy was supplied where a supplemental policy is required.

What to check

• Verify the role of the policy package and the deployment target that received it.
• Confirm that the intended base policy is already active before adding supplemental content.
• Use the policy owner’s approved package instead of converting or reusing a base policy as supplemental content.

Read-only checks

Get-SecureBootPolicy | Format-List

This is the inverse policy-role mismatch: Windows expected a supplement linked to the active base policy. Use the intended supplemental package rather than repackaging or renaming the base-policy file.

Microsoft: Get-SecureBootPolicy

Microsoft: Set-SecureBootUEFI

Microsoft: Secure Boot