macOS offers a number of drive encryption options. With a Mac with a T2 chip built in, the startup volume is always encrypted. On other Macs, enabling FileVault encrypts that volume. (On all Macs, FileVault provides additional protection for a powered-down Mac, too.) You can also select a drive in the Finder, Control-click it, and choose Encrypt “drive name”, setting a password of your choosing.
If you forget that password or were given or purchase a drive that’s encrypted, you might think you’re at a dead end. However, it’s not dire—so long as you don’t need the data on the drive. If you merely want to erase it, Disk Utility will oblige:
Launch Applications > Utilities > Disk Utility.
Select the volume or drive in the sidebar. (See sidebar notes below.)
Choose the format, if you need to change it, and click Erase, and follow prompts.
The newly formatted drive is available for use and has no password attached.
On the matter of the sidebar: If you don’t see the sidebar in Disk Utility, choose View > Show Sidebar. The sidebar also shows only logical volumes by default, or the segments of a drive that mount in the Finder as unique items. To show containers and drives, choose View > Show All Devices. This can make it easier to ensure you’re erasing the correct volume.
This Mac 911 article is in response to a question submitted by Macworld reader Estelle.
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