Sect Mac OS X Extended or Journaled from the Format drop-down menu and then select Erase.ĥ. Once you have selected your USB flash drive, click Erase.Ĥ. Select your USB flash drive from the list of drives that are attached to your Mac. Choose Disk Utility and then click Continue.ģ. You will know that startup is complete once you see the Utilities window.Ģ. If you are being prompted for a password, just type it in. Once you see a startup screen such as a spinning globe or the Apple logo, you can then release the keys that you have been holding down. To do this, restart your Mac and then press and hold Command + R immediately while your Mac is still restarting. Plug in your USB drive and then start your Mac via macOS Recovery. To format your USB drive, follow the steps below:ġ. However, it’s important to remember that formatting your USB drive will delete all of the data on it, so make sure to back up your data first! This is because you want to make sure that the drive is completely clean and free of any viruses or malware. The first thing you need to do before you start the whole process is to format your USB drive. All you need is a USB flash drive that is at least 16 GB in size and a computer running the latest version of Mac OS. How Do I Create An Emergency Mac OS Boot Device?Ĭreating an emergency Mac OS boot device is actually pretty simple. This way, if your computer gets lost or stolen, you will still be able to access your data. This way, if something goes wrong, you will have a backup that you can use to start your computer.Ĭreating an emergency boot device is also a good idea if you are going to be traveling with your computer. You should create an emergency Mac OS boot device any time you are going to be working on your computer’s hard drive or installing a new version of the operating system. In What Instances Do I Need To Create An Emergency Mac OS Boot Device? In short, USB flash drives are easy to use and very convenient at the same time. Finally, most modern computers have USB ports, so you will not need any special adapters or cables to use a flash drive. First, flash drives are small and easy to carry around with you. There are several reasons why you might want to use a USB flash drive to create an emergency Mac OS boot device. RELATED : How To Add A Folder To The Favorites In Mac Finder: A Step-by-Step Guide Why Use A USB Flash Drive?

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