Several months ago I wrote a series on DIY email encryption. One of the steps in this process was installing Gnu Privacy Guard (GPG). This is the free, open-source program that actually manages the cryptographic functions of encrypting your emails. Fortunately, if you have GPG installed, you also have a powerful tool for encrypting files locally. Mac GPG file encryption is really simple to use and provides really strong protection for your data-at-rest.
Encrypting with Mac GPG File Encryption
There are mulitple ways to encrypt a file with GPG, including using your private key. This post is going to focus on the simplest and easiest method: symmetric key encryption.
Step 1: Install GPG. The first step (if you don’t already have it) is to download and install GPG. If you run Linux you probably already have it built-in. If you use Windows, GPG4Win from https://www.gpg4win.org/. If you are on Mac, download the GPG Suite from https://gpgtools.org/.
Step 2: Open Terminal. GPG doesn’t come with a front-end. This means there is not graphical user interface (GUI). All functions are run from the Terminal. Again, if you are on Linux you are alreadly familiar with using Terminal. If you are a Mac user you may need some help opening the Terminal. Open Launchpad and click “Other”. Click “Terminal”. Launchpad will close and a Terminal window will open.
- gpg -c C:\Users\admin\Dekstop\example file.pdf
Entering the file pathway can be simplified through the following procedure:
- Type “gpg -c “,
- The drag the file you want encrypted onto the Terminal window. The file pathway will automatically populate.
Next, press Enter. You will be prompted to enter a password twice. When you have entered the password, an encrypted copy of the file will be placed in the same folder as the original.
Decrypting With Mac GPG File Encryption
To decrypt a file protected by GPG, simply double-click the file. You will be prompted to enter your password. An unencrypted version of the file will be written to the same directory location as the encrypted version.
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