If you disable or do not configure this policy setting, the TPM uses the default platform validation profile or the platform validation profile specified by the setup script. A platform validation profile consists of a set of Platform Configuration Register (PCR) indices ranging from 0 to 23, The default platform validation profile secures the encryption key against changes to the Core Root of Trust of Measurement (CRTM), BIOS, and Platform Extensions (PCR 0), the Option ROM Code (PCR 2), the Master Boot Record (MBR) Code (PCR 4), the NTFS Boot Sector (PCR 8), the NTFS Boot Block (PCR 9), the Boot Manager (PCR 10), and the BitLocker Access Control (PCR 11).