You may have to wait several minutes for the contents of your disk to be encrypted, depending on the size of your drive and its speed. To resolve this issue, you need to erase and encrypt the USB drive in Disk Utility.Įnter your password, verify it, add a meaningful password hit if needed, and then click Encrypt Disk to start the encryption process. Note: If you do not see the “Encryption” option in the drop-down menu, your USB flash drive has not been formatted using the GUID partition map. This tool encrypts the data on the removable drive to provide higher data security.Ĭonnect the USB flash drive to your Mac and find its disk icon on the desktop or Finder sidebar, then right-click and select Encrypt “” from the context menu. Its function is similar to BitLocker To Go on the Windows operating system. The contents of the disk will be encrypted, and without the password, no one can access them. How to encrypt a USB/external hard drive in Finder optionįinder uses XTS-AES encryption, allowing you to encrypt USB disks without erasing data. Click the link below to get a step-by-step guide on how to do that: You can encrypt an external hard drive on Mac without erasing using the Disk Utility or Finder options. We’ll show you how to use Mac’s internal encryption program to encrypt a USB flash drive without losing data.