Want to keep a private folder or password protect some files? There are a few easy ways to password protect your files and folders to keep prying eyes out, and for security. While Macs allow you to create password protected disk images with Disk Utility, other 3rd party applications give you more options and features.
Macs come with Disk Utility, an application that allows you to create a new disk image (.dmg) from a folder, password protecting it in the process. Espionage is another application that also allows you to create a password protected disk image (.dmg), however it adds a lot more features.
Your options to password protect your files and folders are 128-bit AES encryption and 256-bit AES encryption. 128-bit is faster, however 256-bit is a lot more secure. Even the National Security Agency (NSA) says it can be used to protect Top Secret classified information. I’m no security expert but that sounds pretty secure to me.
Disk Utility makes it very easy to password protect your files and folders. You can open Disk Utility from the Application/ folder or by searching for it in Spotlight.
Once you’ve opened it, go to the menu bar and select File -> New -> Disk Image from Folder. Doing so will cause a little window to pop up. Select the folder you’d like to encrypt, and then click the “Image” button on the bottom right. In the next window that pops up, you can set the save name of the file and location that it will saved to. Right underneath that is where you can set a password.
If you want to be able to add more content to the password protected disk image folder you have to select read/write beside Image Format.
Next, beside Encryption, select the level of encryption you want. Click “Save”.
The next window to pop up will ask for a password that will be required each time the disk image (.dmg) is opened. Make sure to uncheck “Remember password in my keychain”. Having your keychain remember the password will automatically open the disk image on your Mac without asking for a password.
Espionage is a paid application, they do however offer a 14 day free unrestricted trial. It has a very simple and easy to use interface. Simply click on the menu bar icon, enter your password and view all your password protected folders. Creating new password protected files is just as easy, just drag and drop your desired folder into the menu bar drop down window.
Espionage will automatically start encrypting the folder and its contents. When an item is turned off (unmounted), that folder can still be seen, however opening the folder will just show an empty folder. Once you switch the folder on in Espionage, it will mount the disk image folder and all the content will be shown.
I think the coolest feature is how it incorporates plausible deniability. I’ll explain; you can set multiple passwords in Espionage, each password having its own unique set of password protected folders.
So for instance, lets say I have two passwords, one is password1 and the other password2. If I enter password1 it will show only the folders that that one password protects. If I enter password2 it will only show the folders related to that password and not password1.
This comes in handy if someone ever asks, “Hey, so what are you trying to hide? Dirty pictures?”. You could answer, “No, just my taxes folder”. If they ask for proof just enter your password for the taxes folder. They never have to know that you secretly have a dirty pictures folder… unless they also read this article and put the pieces together.
Espionage 3 does not allow you to password protect applications, Espionage 2 does. Password protecting an application like Mail for example, will cause a your password to be required before Mail can open. Espionage 2 has the same level of encryption, and is cheaper, although it is missing the easy to use menu bar icon that Espionage 3 has.
I find Disk Utility works perfectly fine to password protect files and folders. It even allows you to send compressed disk images to someone else while still requiring that person to enter the password to open it.
Windows users can’t open disk image (.dmg) files. If you want to send a PC user a compressed password protected file, you should send them a password protected .zip or .rar file. Read more about zipping files here: Compress (Zip) Files and Folders on your Mac
If you deal with many hidden files and folders on a daily basis however, I’d recommend using Espionage. Before purchasing their app though, be sure to check over version 2 and version 3. Both are quite a bit different from each other.