A FileVault 2-encrypted startup disk can be unlocked using a recovery key provided by CIS if a Mac user's password is forgotten. For information on retrieving a recovery key, click here.
To unlock and access the startup disk's FileVault-encrypted data:
1. On the client Mac, start up from macOS Recovery by holding Command-R during startup.
2. Select "Disk Utility" and click "Continue".
3. Select startup disk in left-hand sidebar and click "Mount".
4. Enter recovery key in password field and click "Unlock".
5. Use Disk Utility to save image of startup disk to external drive or quit Disk Utility and open Terminal to use ditto to copy data to external drive.
To unlock and boot a FileVault-encrypted startup disk:
1. On the client Mac, start up from the startup disk and from the login screen, click the "?" button in the "Enter Password" field.
2. Click the ">" button following "...reset it using your Recovery Key"
3. Enter the recovery key.
4. Follow the onscreen instructions to create a new password if desired, then click "Reset Password" when done.
5. Click "Cancel" to permit login using alternate user credentials.