Encrypt an external drive

Have an external drive with sensitive data? Mac OS X Lion and OS X Mountain Lion support full disk encryption. Just right-click (or control-click) the disk in Finder and choose Encrypt. You can continue to use the drive while encryption takes place. Be sure to read these notes:

  • If you ever forget your password there is no way to recover your data.
  • Only Lion and Mountain Lion systems can read these drives.
  • Once the drive is loaded on your computer, other users (including guest) can access the content.
  • This only works with Mac-formatted file systems with a GUID partition map. If your drive doesn’t have both the “Encrypt” option will not appear. You will need to back up your files and re-format using Disk Utility.

Ecrypt external drive