We all know that BitLocker drive encryption helps you protect your data in encrypted form. You can also encrypt the operating system volume with BitLocker as mentioned in this guide. When you encrypt a drive, you must properly backup its recovery key and password, else it would be difficult to decrypt or access the drive.
Consider a scenario, that you’ve encrypted a non-OS drive with BitLocker. While setting up BitLocker, you forget to backup your recovery key. Due to some circumstances, you required to erase the encrypted drive and you did that. Later, you want to encrypt that same drive again. However, when you follow the Bitlocker setup wizard, you receive following error:
The drive encryption algorithm and key cannot be set on a previously encrypted drive. To encrypt this drive with BitLocker Drive Encryption, remove the previous encryption and then turn on BitLocker.
Due to this error, you cannot setup BitLocker encryption on the drive again. If you’re also somehow got into this situation, you can refer below mentioned suggestions.
FIX: The Drive Encryption Algorithm And Key Cannot Be Set On Previously Encrypted Drive
1. Boot to Advanced Recovery Options screen.
2. Select Command Prompt option in Advanced options screen.
3. Log in to Command Prompt with your account.
4. In Command Prompt window, type following command and press Enter key:
manage-bde -status <drive>
Note: Replace <drive> with actual drive in question.
5. Since we’re facing issue with non-OS drive, hence it shouldn’t be locked in pre-boot environment. You can type following command after substituting correct drive letter and suspend protection:
manage-bde -protectors -disable <drive>
6. Now close Command Prompt and continue to the operating system.
7. If system reboots, login and then try enabling BitLocker encryption on the non-OS drive. This time it should work without any error.
Let me know via your comments, if issue still persists!