How To Burn Mountain Lion To A DVD Or USB Flash Drive

How To Burn Mountain Lion To A DVD Or USB Flash Drive

Mac: You can easily download Mac OS X Mountain Lion from the App Store any time after purchasing it, but if you want your own physical copy of the installation, here’s how to make your own Mountain Lion install DVD or USB drive.

Having the installer on physical media is necessary if you ever want to do a clean install of the operating system or install it on a hackintosh.

As with last year’s Lion upgrade, after you run the installer on your system, it disappears from your Applications folder. You can restore by holding down the Option key while clicking on the purchases tab to re-download the file or restore the installer from a Time Machine backup. However, to save time, it’s best to do this disc burning before you update your Mac to Mountain Lion.

MORE:Everything You Need To Know About Mac OS X Mountain LionInstall Mountain Lion On As Many Macs As You Want Without Purchasing Additional Copies

The Easy Option: Use Lion DiskMaker

Lion Disk Maker is a donationware app from Serial Server. Version 2rc2 burns Mountain Lion or Lion to an external drive or DVD. You’ll need at least an 8GB USB flash drive, USB/Firewire drive or SD card to make the bootable disk or a single-layer or dual-layer writable DVD. Note that the program will overwrite all files on your USB drive or SD card when creating the bootable disk.

Lion Disk Maker finds your copy of Lion downloaded to your Applications folder, asks you what media type you want to use to create the install disk, then handles the rest.

DIY Option: Use OS X’s Built-in Disk Utility

The steps for burning Mountain Lion to disk are essentially the same as the ones used for Lion:

  1. Download Lion from the Mac App Store — but don’t install it yet (because of the disappearing installer issue noted above).
  2. Find the installer in your Applications folder and right-click on it then select “Show Package Contents”. Head to Contents > SharedSupport and look for the file called “InstallESD.dmg”
  3. Open up Disk Utility from your Applications > Utilities folder and drag the DMG file into the sidebar on the left.
  4. If you’re burning to DVD: insert your disc, select the DMG file in the sidebar, and click on “Burn”. Skip to step 6.
  5. If you’re burning to USB, you’ll need to first format the drive properly:
    • Insert the disk and select it in the sidebar in Disk Utility. Select the Partition tab, select “1 Partition” from the dropdown menu and choose “Mac OS Extended (Journaled)” for the format type.
    • Click the Options button and choose “GUID Partition Table” — this will make the drive bootable and formatted correctly for the Mac. Hit Apply to format the drive (this will completely erase it).
    • Now click the Restore tab and choose the DMG file as your source and the USB drive as the destination. Hit the Apply button to complete the process.
  6. Finally, to boot from your install disk/drive and install Mountain Lion, restart your Mac and hold the Option key down when you hear the startup chime.

Besides installing Mountain Lion, your installer disk/drive will have a number of handy utilities on it, including Disk Utility and Time Machine recovery.

When you install Mountain Lion, you’ll have a recovery partition on your drive in case something goes wrong. That said, it’s always nice to have a disc or flash drive handy in the event you need to perform a clean install.


  • It should be noted that, when using a standard 4.7GB DVD disc, Disk Utility gives an error that there is not enough free space on the disc.

    • Someone posted the following on another site in the comments:
      If you have a normal DVD, you can create an empty image of a single partion dvd with Disk Utility, name it OSX Lion Mountain DVD. (Size 4.6 Gb)

      Then mount the installESD.dmg

      You should have 2 drives on your desktop.

      The insall DVD img you made (empty)

      The Mac OS X install ESD of 4.75Gb

      Now, the problem is Apple did a dmg of 4.75gb and the used space in it is only 4.3gb. So Disk Utility see only the total capacity of the dmg (4.75) and tell you you cant burn it to a normal dvd.

      to solve that:

      open Terminal and type

      cp -Rv /Volumes/Mac OS X Install ESD/* /Volumes/OSX Lion Mountain DVD

      This will copy all the content of the apple install dmg into your new image.

      You can see that everything was able to fit 😉

      Now burn this image to a DVD and voila.
      To be honest, I have yet to test it.

      Source: Benoit @

      (If the author here doesn’t like that I link to another site, please feel free to simply delete this)

      • Thanks a ton for this post – Saved plenty of download time

        Just for future reference the terminal command it inccorrect – Check the page (it contains backslashes)
        “cp -Rv /Volumes/Mac\ OS\ X\ Install\ ESD/* /Volumes/OSX\ Mountain\ Lion\ DVD/”

      • Nice try, but I think something is missing. The DVD is NOT bootable.
        It all copied, and I burnt the disc fine, checked that all the files were there, looks fine.
        When I insert the DVD and reboot, hold option, all the hard drives come up in the list, but no DVD.
        Maybe there’s something else that has to be done to make it bootable?

        • Hi Fred,
          I bought and installed it. Safari is driving me nuts and a minor niggle is it constantly loses the link between the dock icons for Aperture (another genuine recent purchase), Mail, Contacts/Address book and one more I forget. So I’m currently redownloading it and going to try to make a bootable disk.
          I’ve not tried this but: When I bought this MacBook Pro about 2 weeks before the Retina and new version were released (my lack of research), I made a Lion bootable USB Flash using the App for this from the Apple web site.
          I’m thinking: for Frank’s DVD solution (thanks Frank), should we/can we format the single partition in the ‘GUID’ Bootable format option available in disk utility?
          I haven’t tried it, but will when the (re) download stops.
          Apple: I’ve been maintaining your various Power/Mac Books at various universities since 1995. It isn’y me main job. One thing that made it easier from around os 8.6 onwards (maybe higher) was the inclusion with each machine of a circle of plastic worth about 12c. A system restore CD then from about 10.4 a restore DVD.
          OK, environmentally unfriendly, but so is excess electrical energy used by brand new, in warranty computers repeatedly and often in an act of futility, downloading 4.4 gig of data literally millions of times. Good work with the virtually unrepairable retina 15″ with its lovely batteries.
          Thousands of dollars, recommendations, 17 years of loyalty.
          Remember the ‘Think different’ campaign?
          Please starting thinking differently in different ways.
          By the way ‘We don’t do beige’ is forgotten. You do silver grey, white and some mainly black trim.
          The ‘Aldi’ $350 garbage Windows based laptops from china are selling by the shedload; and they’re often interesting colours.
          I never used to associate a company I love with the increasing sterile greys, aluminium’s, blacks and whites of modern society.
          Anyway Fred, that off my chest, I’ll carry on wasting valuable life hours trying to make a useful coaster;-)

  • It’s ok. Found it. It is in Applications – named ‘Install OS X Mountain Lion’.

    It is not able to be found with the integrated search bar in Finder. You can only find it using Spotlight.

  • I am following these instructions very carefully to burn to a USB (except at the end, the only instruction available is not “Apply” but “Restore”) and I keep on getting a failure because of an “unable to restore because of invalid argument”. I am using a 32 gig usb and formatting it with Mac OS Extended (Journaled) and GUID Partition Table. What am I doing wrong?

  • There’s a missing step here for ML to USB using Disk Utility. After you’ve dragged the .dmg into Disk Utility, you need to double-click it to mount it. Then you restore the resulting mount (Mac OS X Install ESD) to your USB.

  • Hi guys,
    I did the same thing to make the bootable disk, but I could not make it.
    So here is the solution for getting the software and install it on your mac computer for free.
    For doing this you need two mac PC or laptops.
    Just buy the OSX lion on one computer but don’t install it right now .
    After that open your other computer and go in air drop, now go in application folder of the computer where you already have the OSX mount lion. You do not need to open the package content.
    By using the air drop send the file from one computer to other computer, it will take some time because of size of the file.
    Now you can install the OSX software in your computer. After installing the software just Update your computer and now you can also download the software so many time from app store by using your apple ID and its free.

  • Trying to upgrade an aluminum body MacBook (which apple lists as supported for mt. Lion) but it is not working. The install disk works just fine and I run through the process, but where I need to select a disk to instal it on the HD is greyed out and says “You can’t upgrade this version of OS X”

    • Not unless they are in the same household as you….

      So if you have 3 Macs on your network, you only need to download one copy (and as soon as the download finishes – copy the file somewhere else so you don’t have to redownload it).

      If you have one Mac and your family (living next door) have 3 macs – you have to download it once, and your family has to download it once.

      Having said all of that – if you have a copy of the downloaded “Install” on a USB, then it can be installed on as many Macs as your conscience can bear….

  • I have a 16 Gb Sandisk USB Flash drive. I’ve tried the Lion Disk Maker Version 2rc2 and it failed to create a boot disk from my Mountain Lion download.

    I then tried the DIY process following the steps exactly but when it exited the RESTORE step after 25 minutes, it also failed and gave an error as well “Could not restore – Invalid argument”…

    Can anyone help?

    Thanks …


    • Did you mount InstallESD.dmg before using it as a source for your USB drive? If you use InstallESD.dmg as the source it can sometime give the error you describe, whilst mounting it and using the mounted volume as source does not give an error.

  • Thanks ! I was missing the mounting part. Mounting InstallESD.dmg did the trick. Silly that the disk utility gives you the error message just at the end …

  • followed the steps in the hightechdad article and replaced the
    terminal command with the one from this lifehacker post and it all
    worked fine. Cheers!

    • You can hold down option and click purchases in the app store however this works if you bought mountain lion and installed it already, I don’t know if it works if it was already installed. Doesn’t your Mac come with an install USB already?

  • I thought I was unable to drag the DMG file to the Source field in Disk Utility that’s what brought me to this forum. I would drag the file to the field and drop it and seemlingly nothing happened. But after a few minutes I looked back and noticed the InstallESD.dmg file was sitting there in the Source Field, maybe it just needed some transfer time?

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