On system drives that have been encrypted with Bitlocker to enable pre-boot authentication, users may at one time or another find themselves locked out from the computer. If too may pin entry attempts are made by the user, an administrator will have to enter the recovery key to get it going again. Additionally, the administrator will have to reset TPM Lockout; otherwise, the user will continue to be prompted with the message: Too Many Pin Entry Attempts. Subsequently, you will have to enter the recovery key in order to complete the boot process until TPM Lockout has been reset.
When using Bitlocker preboot authentication on a Windows 8 machine, it is very important for the Recovery Key to be saved to a safe place, preferably, a central repository where administration can have access to all Recovery Keys when needed (and they eventually will). BitLocker gives you several options to saving the Recovery Key when enabling pre-boot authentication for a system drive.
Sometimes a user will enter the proper BitLocker PIN at boot but find themselves with a message stating ” Too Many Pin Entry Attempts”. If you see this message you will need to reset TPM Lockout once you are logged in to the system. To log in to the system you will have to enter the BitLocker Recovery Key that was saved when encrypting the system drive. Once you have located the Recovery Key and have gained access to the system, right click on the C: drive and select Manage BitLocker. On the Drive Encryption Window, on the bottom left hand corner click on TPM Administration. In the Trusted Platform Module (TPM) Management on Local Computer window click on Reset TPM Lockout.
The system will again display Enter the PIN to unlock this drive and will accept the BitLocker PIN at boot.