How to Make Mac OS X Lion 10.7 Bootable USB Flash Drive

Apple Mac OS X Lion is now available to general public. The Mac OS X 10.7 Lion is available for installation only from the Mac App Store. This guide will teach you how to create a bootable USB Flash drive of Mac OS X Lion 10.7 and install Lion from USB, rather than downloading it from Mac App Store on each and every Mac computer you own.

Despite of numerous great and awesome features, Mac OSX Lion 10.7 has a big flaw that it is not available in bootable USB or DVD right now. Every time you you want to install OSX Lion on a Mac you will need to download it from Mac App Store all over again. Thanks to the bootable USB method which eliminates the downloading of Mac OS X Lion for each and every device and lets you install Mac OS X Lion on any Mac.

Note: An official bootable USB of Mac OSX ion 10.7 will be available in August 2011 for $69. This method not only eliminates the wait for the official, it also saves you $40 (Mac App Store version costs $29).

Creating a bootable Mac OS X Lion 10.7 USB Flash drives requires medium level Mac knowledge, however, by following these simple instructions even a beginner should be able to install Mac OS X Lion via USB Flash Drive.

Why make a bootable Lion USB drive?

  • You can perform a clean OS X Lion installation with the bootable USB drive
  • The bootable Lion USB drive becomes a recovery disk with Disk Utility access, access to Time Machine backups, re-installation, and all other Recovery HD partition features
  • You will have external media to recover and reinstall Lion in the event of total drive failure or some other catastrophe

Required Stuff

If you have arranged the above mentioned items, simply follow the detailed guide below to create a bootable Mac OS X Lion 10.7 USB Flash Drive…

How to Make Mac OS X Lion Bootable USB Flash Drive

Step 1 – Locate the Lion InstallESD.dmg file

Once the Lion downloading is complete, go to the Applications folder and find the Install Mac OS X Lion.app file you just downloaded;
Right click on the Install Mac OS X Lion.app file and select Show Package Contents;

OS X Lion Show Package Content
Now go to Contents > SharedSupport directory. Locate the file named: InstallESD.dmg and copy it on your desktop.

InstallESD.dmg file

Copying file

Step 2 – Format The USB

  1. Before formatting, If you have any data on your USB drive then save it;
  2. Plug the USB flash drive into your Mac;
  3. Launch Disk Utility from Applications;
  4. Select the plugged USB from the Left pane on the Disk Utility and click on Partition tab;
  5. Select 1 Partition from the Volume Scheme dropdown menu;
  6. Input a name for the USB and Choose Mac OS Extended (Journaled);
  7. Now click on Options button at the bottom. Select GUID Partition Table and click OK. Now click on Apply at the bottom right to start formatting.

OS X DiskUtility create partition

Step 3 – Make Mac OS X Lion Bootable USB

  1. Double-click on InstallESD.dmg (that you copied onto your Mac desktop) to mount the Lion disk image (mounted InstallESD.dmg should appear on Disk Utility application and desktop);
  2. Select the plugged USB from the Left pane on the Disk Utility and then go to Restore tab;
  3. Click and drag the IMac OS X Install ESD from the left pane and drop it in the Source field;
  4. Then Click and Drag the USB drive from the left pane and drop it in the Destination field;
  5. Make sure you have chosen the right USB drive, you don’t want to format the wrong drive and then click on Restore button;
  6. This will restore the Lion 10.7 image to the USB Flash drive. Wait for the process to complete.

Disk Utility Restore

 Step 4 – Boot Mac OS X Lion from USB

  1. Reboot your Mac with the USB drive plugged in.
  2. Hold down the alt/Option key on your keyboard when you hear the OS X start-up sound.
  3. Choose the USB Flash Drive from there to boot.
  4. Now follow the on screen instructions to install OS X Lion.

OS X Boot Option

Mac OS X Utilities

Mac OS X Lion Setup

You can follow the Step 4 to install Lion on other Macs with the bootable USB you just created.

[via Lifehacker]

8 comments… add one

hankeypank August 31, 2011, 2:17 am

All procedures followed to the letter yet at the end the “restore” button is grey out and not functional. The SanDisk USB drive was formatted in one partition which ended up at 7.69 GB.

I am running OSX 10.6.8

LesliePooPoo September 11, 2011, 8:25 pm

This only works if you have the recovery partition present on a drive installed in the computer you are wishing to restore. If this partition is not present the method explained above will not work!

Think I’m right.

Hope I’m wrong…

Raxonon September 15, 2011, 11:37 am

Thanks for the trick. Its really of great use. Although I haven’t created bootable USB for Mac Lion but created a bootable disk for Mac OS X 10.7.

I did it with Stellar Drive Clone. One can select to create a clone of either the entire disk with all the applications installed in it OR create a minimal system with selective applications in it.

Will October 12, 2011, 9:57 pm

I’d like to know how we might create such a bootable USB drive from a new Mac that already has Lion installed on it. Anyone have knowledge about how to do that?

username November 17, 2011, 11:18 pm

alt/option click purchased in the app store, the install button will be available this way so you can redownload the install package.

Perlao December 28, 2011, 2:22 am

It worked like a charm!! there’re not kind enough words of gratitute for you, greatly appreciated

titish September 19, 2012, 2:02 am

Is theer any chance to build mac osx mountain lion into usb while on pc running windows xp

prd August 11, 2013, 1:31 am

thanks for the guide but the USB doesn’t work on all macbook models…

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