BitLocker Password Key Viewer is the FREE software to instantly recover the BitLocker password key for all protected drives. It support all hard drives, external disk, USB flash drive etc
For each protected drive, it displays Drive Name, Drive Volume Type, Encryption, Key ID and BitLocker Key Password.
Based are the possible values for "Drive Volume Type" based on type of drive
OSV => Operating System Volume
FDV => Fixed Disk Volume
RDV => Removable Data Volume (for external USB drives, etc.)
Once recovered, you can backup all BitLocker keys to HTML file for safe keeping.