Solution:
Root Cause: Unregistered Local BitLocker Backup or Active Directory Group Policy Storage
If the system is joined to a traditional Active Directory Domain, Group Policy forces BitLocker recovery information into Active Directory Domain Services (AD DS) objects. On local accounts, keys were exported to a TXT file, USB drive, or printed document.
Step-by-Step Fix:
1.Query Active Directory via PowerShell (For IT Admins):
On a Domain Controller or machine with RSAT installed, open PowerShell as Admin.Retrieve the BitLocker recovery password using the computer name: powershell
Get-ADDevice -Filter "Name -eq 'COMPUTERNAME'" -Properties * | Select-Object -ExpandProperty msFVE-RecoveryPassword
Alternatively, use Active Directory Users and Computers, right-click the domain root, select Find BitLocker Recovery Password, and input the 8-character Key ID from the boot screen.2.Scan External USB Drives and Local Backups:
Insert potential USB backup drives into a working PC and search for files matching BitLocker Recovery Key *.TXT.Open the text file and verify the Identifier field matches the Key ID on the locked screen.3.Force Unlock and Update Key Protectors:
Boot into WinPE Command Prompt on the target machine and run: cmd
manage-bde -unlock C: -recoverypassword [48-digit-key]
manage-bde -protectors -delete C: -type RecoveryPassword
manage-bde -protectors -add C: -recoverypassword