How to Make an OS X Recovery USB Drive

  Matt Cone       January 17, 2013      Tutorials Mac


It’s a good idea to have a bootable emergency drive on hand, just in case disaster strikes your Mac. An emergency drive (also referred to as an OS X Recovery Disk) can help you repair the hard disk, reinstall the operating system, and restore from a Time Machine backup to get your computer back fast.

Mac OS X logo

With previous versions of OS X, you could have used the installation DVD to fix problems. But OS X Mountain Lion is sold in the App Store as a digital download — no physical disk is provided. What’s a maintenance-minded Mac user to do?

Create your own bootable OS X USB drive, of course! It’s easy, and if you’ve already purchased OS X and have a USB drive that’s 1 GB or larger, it’s completely free. Carry it in your pocket or put it on your keychain so it’s available if the worst-case scenario occurs. You’ll thank yourself for taking the time to complete this project.

Evaluating Your Emergency Drive Options

It can happen to any of us, even those who own brand-new Macs. First your computer starts freezing infrequently, then crashing more often, and then it won’t start at all. For situations like this, you need an emergency drive on hand to start up your computer and troubleshoot the problem.

Purchasing a USB Drive for Your OS X Recovery Disk

If you don’t have a spare USB drive, you’ll need to purchase one. We recommend the Amazon Basics 8 GB USB Flash Drive, which is a simple and affordable option available for less than $10.

USB thumb drive

Making Your Own Emergency OS X USB Drive

The best option is a Recovery HD partition on a bootable USB drive. This drive provides you with all the tools you need to troubleshoot problems, repair the hard drive, reinstall OS X, and restore from a Time Machine backup. In short, it’s the perfect safety net for those rare times when your internal hard drive is hosed.

Here’s how to create an emergency USB drive:

  1. Connect a hard drive or USB drive to your computer. If the drive is larger than 1 GB, consider partitioning it to make a 1 GB partition for the recovery disk. (If you don’t create a partition, this process will use all of the available space on the drive, no matter how large it is.)

  2. Open the Recovery Disk Assistant application. It’s available for free from Apple’s website.

  3. Accept the license agreement. The Recovery Disk Assistant window appears, as shown below.

    OS X Recovery Disk Assistant

  4. Select the disk and then click Continue.

  5. Authenticate with your administrator username and password. The Recovery Disk Assistant creates the recovery disk, as shown below. The process takes approximately five minutes.

    OS X Recovery Disk Assistant

  6. When the recovery disk has been created, click Quit.

Like the Recovery HD partition on your startup drive, the emergency drive is invisible when it’s connected to your computer. The Finder won’t provide any indication that it exists, but don’t worry — it’s there, waiting for your signal to help with a disaster!

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