Erasing a FileVault 2-encrypted Volume on the Mac Since the introduction of OS X 10.10 Yosemite, Apple encourage its users to enable the FileVault 2 protection for their hard drive. However, it is aware that if the hard drive was erased without decrypting, it would cause some issues when you reinstall OS/reclone the image on it. This guide is to assist you to troubleshoot if FileVault 2 was enable on the hard drive and erasing FileVault2-enabled hard drive with no issues. Path:

1. Open Terminal app in the Utility folder. 
 2. Type the following command to determine if FileVault 2 is enable. Press Return. sudo fdesetup status 3. After pressing Return, it prompts for the admin password. Type the password to continue.

4. There are only 2 possible responses to the command. FileVault is On. FileVault is Off. 5. Click Restart under the drop-down list of Apple icon. Upon you hear the chime sound, press ‘Command + R’ to perform the internet recovery. The recovery partition will then immediately be built. 6. When booting into the recovery partition, click Utilities and select Terminal to continue.

7. Type the following command to display a list of the CoreStorage volumes on the system. diskutil cs list Unless there is a Fusion Drive/multiple encrypted drives, it should only show one FileVault 2 encrypted drive.

8. Now, go to highlight and copy the UUID of the Logical Volume Group.

9. Next, type the following command to delete the Logical Volume Group. Press Return. diskutil cs delete (UUID_here) In this example, it should be as following: diskutil cs delete 6EB5DB8E-D2E6-4C3E-B65C-B015ED22E78D

10. Upon you press Return, the terminal starts to delete the CoreStorage volume and reformat it as an unencrypted HFS+ volume.

11. The hard drive has been reformat, you can now reinstall OS/reclone the corresponding image on it.