“Hey Christian! I have some files on my Mac that I don’t want falling into the wrong hands. Is there an application that I can use to password protect them? Thanks!” – AH

We all have files, pictures and personal information that we’d like to keep from prying eyes. This is particularly true if you are a mobile user. Your Mac comes with lots of built-in security features to protect your personal data, but many of those features require that you logout of your user before they are 100% secure. Some of us, like myself, just have a few documents that contain data we’d rather not fall into the wrong hands, but use regularly. I’m often asked if there is a way or an application that will “lock” certain folders on your Mac so that only you have access.

Well, I can’t say that I’ve used any stellar software that will help with this. I’ve heard most people recommend that you simply “hide” your folder/documents by making them invisible (with a simple applescript). Granted, if people don’t see anything on you desktop they presumably won’t know anything is there, but what about that one clever individual that does know how to “show hidden files?” This is a stupid idea isn’t a very safe option in my mind.

This tutorial is designed to show you how to create a password-protected, encrypted partition to help you securely store your personal files. The process takes just a few minutes to set up, and is 100% free. Your Mac has everything you need, built right in.

Before we get started, let me talk for just a minute about partitions:
Some of you will understand the term, but many will not. Partitions, by definition, are elements divided from a larger whole. With computers, many users will “partition” their hard drive. This allows you to make “two” virtual drives out of one physical drive. And, you aren’t limited. You could partition a drive into an endless number of pieces. The question is, why would you?

Many Mac users have their primary (installed) hard drive partitioned if they have installed a copy of Windows (using Apple’s Boot Camp). This division helps keep the Windows files from mixing their way into, or effecting, the Mac’s OS files.

In this particular example, we are going to create a partition that will act like a virtual hard drive; it’s called a “Virtual Drive Partition,” or VDP for short. You’re probably already familiar with these virtual drive’s as many Mac applications use this exact process to deliver their apps to you when you download from online sites.

You know the deal: you download a file that ends in “.dmg” and once it’s complete a little white drive appears on your desktop and a window opens. You drag the app to your applications folder, and once it’s done copying, you eject the white drive icon, and throw away the DMG file. The FireFox images below are a perfect visual example. Please note that FireFox has used a custom icon to change the “white” default drive to a blue-logo icon:

These little “virtual drive partitions” are helpful because they can be compressed, and make it much easier for developers to distribute their applications through the web.

We are going to create a VDP ourselves, we just don’t plan on sharing it with anyone!

Let’s get started:
First launch the Disk Utility application. You can find it in Applications >> Utilities, or through my preferred method: Spotlight! Here’s how: press the command + spacebar for the spotlight queue to open:

Type, “disk utility.”
As you begin typing, you’ll notice that your Mac begins to populate the dropdown with suggestions. Often getting it right before you finish typing. Once you see “Disk Utility” at the top of the list, press the return key to launch it.

As a side note, this is an excellent way to launch any application on your Mac, without having to bury through folders in the Finder.

The Disk Utility window may appear a little intimidating, but don’t be scared. We’re going to do some basic stuff and close it down.

At the top of the window click “New Image.”

A sheet will drop down where we are going to customize our virtual drive partition. Keep in mind that you may want to adapt some of these for your own personal needs, including the size. If you are only storing sensitive documents, you don’t need a 100MB partition. You can literally store HUNDREDS of documents on just 40MB. Your sheet should look something like this:

Make sure that you choose SOME level of encryption. 128-bit AES is a standard, government approved level of security. If you are super-paranoid you can choose 256-bit, but I don’t think it’s really necessary. When you are done, click “create.”

You will see a progress bar on your screen and after a moment, a password dialogue box. This is where you will enter the password that is going to protect this partition. As always, try to be creative with your password, incorporating letters and numbers. Your Mac even gives you a “strength meter” to help you determine the quality of your password at a glance.

ALSO, DO NOT check off the “Remember password in keychain” box. Deselect it IF it is checked. Click “Ok” when you are done.
You can now Quit the Disk Utility and head back to the desktop.

On your desktop you should see two new icons: one is the “dmg” file; the other is the “virtual drive partition.”

We’re ready to start using them.

Anything you drag onto the VDP will be copied (it’s acting like a hard drive) and encrypted. Copy as many files onto the drive as you’d like (space permitting): personal documents, photos, whatever. You can also create folders and organize as you see fit. This virtual drive will act just like a normal jump/stick drive you might plug into your Mac.

Once you have added all the files you are looking to secure, you can eject the VDP.[1] Be aware that although you are “ejecting” a drive, nothing will spit out of your Mac. This is a “virtual” drive.

You can now store the “dmg” file anywhere you’d like: in your documents folder, on the desktop, in your dock, anywhere. Just be sure NOT to delete it, as all your files will be trashed (securely) with it. The next time you need to access the secured files, or add to or modify those already protected, simply double-click the DMG file. You will be prompted for your password:

Once entered correctly, the VDP will mount on your desktop. All you have to do to protect the files or safeguard the information on it, is to eject the virtual volume. Some people (like myself) go one step further and customize the default drive icon so that they can tell (at a glance) if the drive is mounted before walking away from the computer. More on how to do that later…

That’s it!

I don’t need the files in my protected drive often, but I like to have them handy when I do, and secure when I don’t. I keep my dmg in my dock & open it when I need something. This is particularly helpful on my MacBook Pro. If I ever lost the computer, I could sleep at night knowing that my most crucial personal data is secure. Finally, make sure you don’t forget your password. There is NO WAY to recover it if forgotten! And, you’ll lose access to all the files in your VDP.

Questions? Don’t hesitate to ask.

Are you following MUM on Twitter?

---

[1] For those unfamiliar with ejecting a drive/disk: click on the icon and press command + E, or click and drag the drive icon to the trash. The trash will turn into an eject symbol. When you drag the drive icon onto the eject symbol, it will eject the volume.