In macOS Mojave, you can choose to encrypt and decrypt disks on the fly right from the desktop. Using this convenient Finder option, we’re going to show you how to encrypt a USB flash drive (or “thumb drive”), which is useful if you’re traveling light and want to take sensitive data with you for use on another Mac.
Finder uses XTS-AES encryption, the same encryption that FileVault 2 uses to prevent access to data on a Mac’s startup disk without a password. Note that the following method is only compatible with Macs – you won’t be able to access data on the encrypted drive using a Windows machine.
If this is a requirement, you’ll need to use a third-party encryption solution like VeraCrypt. With that in mind, here’s how to securely encrypt your USB flash drive.
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