Disk Utility

How to create blank disk images with Disk Utility

Should you ever find yourself in the need to create blank disk images, OS X’s built-in Disk Utility is your friend. A disk image usually has a .dmg extension and appears, looks and behaves like any ordinary file, with one key exception: launching it prompts OS X to mount the volume on the desktop.

These mountable disk images can be useful in a number of situations. For example, you may want to create blank disk images for storage.

Furthermore, disk images can be used as a virtual disk for software distribution, to burn CDs or DVDs and so forth. In this step-by-step tutorial, you’ll learn how to create blank disk images in Disk Utility, at any size, with optional password protection, formatting options and more.

How to repair Mac disk errors in macOS Recovery Mode

The built-in recovery partition on your Mac’s startup disk contains recovery tools, like Disk Utility. Recovery Mode makes it easy to repair your Mac’s disk in situations when the machine won’t boot properly and load the desktop in the first place. We show you how to repair disk error using Recovery Mode.