You can access a BitLocker encrypted drive either using the BitLocker password or the BitLocker drive encryption recovery key. Forgetting the recovery key won't cause a big problem since you still have a password to unlock it. Therefore, go to find the password you created when enabling BitLocker on the HDD. But if you fail with both, try some BitLocker password recovery tools there:
BitCracker, Thegrideon BitLocker Password, Elcomsoft Distributed Password Recovery, and Passware Kit.
For more solutions, please visit: How to Unlock BitLocker Drive Without Password & Recovery Key?
