Mac: How To Encrypt An External Hard Drive In Lion

Most computer users use or carry around some kind of portable hard drive or flash disk these days. Considering how we use our computers, almost all of those portable drives tend to store an alarming amount of sensitive data. Have you ever thought what would happen if you lose the disk and the data gets into the wrong hands ?

There are a lot of software solutions available that’ll let you encrypt the data on your disks but most of them are confusing to use and just a pain really. Not, if you’re a Mac OS X user.

Mac OS X lets you encrypt and password protect the contents of any connected disk. Follow our little guide to know how.

First of all, if it wasn’t obvious, connect your disk (using USB) to your Mac and launch the Disk Utility application.

The Disk Utility application will display all the drives that OS X has recognized on your computer in the sidebar. Select the drive that you want to encrypt.

Note: To Encrypt a drive, OS X has to format it and so you will lose all the existing data on the drive. If there is any important data on the drive, copy it to another location and then copy it back later.

Now, select the Erase tab and from the Format drop down list select “Mac OS Extended (Journaled, Encrypted).

You can also select the Case-Sensitive, Journaled, Encrypted option if you want your file system to be case sensitive.

Now, click the Erase button.

Disk Utility will now ask you to enter a password that you will use to access the contents of the encrypted disk. If you can’t think of a strong and memorable password yourself, I’d definitely suggest using the Password Assistant. Click on the little key icon next to the password text box and play around with the password assistant till you find a nice password that you can remember and one that is secure.

That’s it. Now, wait for Disk Utility to finish partitioning and encrypting the disk.

When the disk is ready for use, as indicated by Disk Utility, I’d suggest that you eject it and insert it again just to check if everything works as it should. If you followed the procedure properly, Mac OS X will ask you for a password to access your disk when you insert it again.

That’s it. Enter your password and you should be able to access the contents of your disk as always. When you’re finished using the disk, make sure you eject it properly so that no one else with access to your computer can access your data.

The only problem with this method of encrypting your external hard disks is that the data on the disk can only be viewed on a Mac OS X computer. Depending on your preferences, though, that may well be a good thing!