Access Keys:
Skip to content (Access Key - 0)

Enable FileVault on External Disks in OS X 10.8 and Up

Use the following steps in OS X Mountain Lion (10.8) and up to encrypt (and decrypt) external disks, including flash drives, from the Finder.

  1. Open a new Finder window and select the external drive you would like to encrypt from the panel on the left, under Devices.
  2. Right-click (or two-finger click, or control-click) on this disk in order to bring up a contextual menu, and then select Encrypt "External Drive Name"...
  3. When prompted to create an encryption password, use a strong password and enter it twice, along with a password hint, and click Encrypt Disk.

    Result: The external disk will begin to encrypt, however, there is no progress bar to show you the process of the encryption, which could take as few as a couple of minutes up to several hours for large disks. The best way to tell that the encryption is taking place is to watch the activity indicator light for your disk, if it has one, and if it is blinking do not disconnect it as the encryption process is likely still in progress.
  4. Once encrypted, when you next plug your external drive in, you will be prompted to enter the password you created earlier and click Unlock in order to unlock the disk. If you would like to skip this step when accessing this disk on your primary Mac, you can choose to select the checkbox to Remember this password in my keychain.
GUID Error Message Resolution

If you at step 3 above you get an error message saying "A GUID Partitioning Table (GPT) partitioning scheme is required.", please go to this Knowledge Base article for a resolution.

IS&T Contributions

Documentation and information provided by IS&T staff members

Last Modified:

December 03, 2013

Get Help

Request help
from the Help Desk
Report a security incident
to the Security Team
mountain mountain Delete
lion lion Delete
mac mac Delete
filevault filevault Delete
encrypt encrypt Delete
disk disk Delete
flash flash Delete
drive drive Delete
osx osx Delete
108 108 Delete
c-filevault c-filevault Delete
Enter labels to add to this page:
Please wait 
Looking for a label? Just start typing.
This product/service is:
Easy to use
Difficult to use

This article is:
Adaptavist Theme Builder (4.2.3) Powered by Atlassian Confluence 3.5.13, the Enterprise Wiki