How to Create a Bootable OS X Mountain Lion USB Install Key
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Posted July 25, 2012 at 6:31pm by iClarified
These are instructions on how to create a bootable OS X Mountain Lion USB key.
Step One Connect a 8GB or larger USB key to your computer then launch the Mac App Store from your dock.
Step Two Click the Purchased tab at top of the window then hold down the Option key and click the Purchased tab again.
**If you have not yet installed Mountain Lion then you can follow these instructions to buy it and begin downloading.
Step Three Press the Install button for OS X Mountain Lion and wait while the operating system downloads. If the LaunchPad appears press the Escape key.
Step Four Once the download has completed the Mac OS X Lion Installer will launch. Select Quit from the Install Mac OS X Lion to exit the installer.
Step Five Click to launch a new Finder window from your dock.
Step Six Navigate to the Applications folder and right click the new "Install OS X Mountain Lion" icon then select Show Package Contents from the contextual menu.
Step Seven Double click the Contents folder.
Step Eight Then double click the SharedSupport folder
Step Nine Right click or 'Control' click InstallESD.dmg and select Disk Utility from the Open With menu.
Step Ten Select your USB thumb drive from the list on the left and click the Partition tab.
Step Eleven Set the Partition Layout to 1 Partition, set the Name to 'MOUNTAINLION', set the Format to Mac OS Extended (Journaled), and then click the Options button.
Step Twelve Choose GUID Partition Table from the popup window then click the OK button.
Step Thirteen Next click the Apply button to save your changes.
When asked to confirm click the Partition button.
Step Fourteen Right click or control-click the InstallESD.dmg image from the left side of Disk Utility and choose Open Disk Image from the popup. Select the new Mac OS X Install ESD partition that appears then click the Restore tab.
Step Fifteen Make sure the Mac OS X Install ESD is set as the Source then drag the MOUNTAINLION partition from the list on the left into the Destination field.
Step Sixteen Click the Restore button then click the Erase button from the confirmation popup to begin building your install key.
Another popup will appear asking you to log in. Enter your administrative username and password then click OK.
Step Seventeen When the restore is complete the OS X Mountain Lion USB Install Key will be mounted and it will be ready to use.
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I read the whole article but, could someone tell me what is the purpose of creating this Bootable USB? I am waiting for apple to send me my code for the upgrade and would like to know what is this about before I upgrade my OS. Thanks in advance!
Having a USB installer is useful for several reasons. Two that come immediately to mind are: 1) It allows you to install Mountain Lion on a computer that is not connected to the internet. 2) It allows you to install or reinstall Mountain Lion on one or more computers, without having to re-download the entire multi-gigabyte image file each time, and for each computer.
Everything went just like described, but when I reboot from the Bootable disk, to do a clean install of Mountain Lion, I get a message saying |There was a problem installing "Mac OS X". Try reinstalling.| Did anyone encounter the same problem and does someone have a solution? Thanks. Gr, Gio
Sorry but my question isn´t about this topic.
Someone know if was fixed the issue when using fullscreen apps on dual displays?
I going to buy another display for my Mac but on Lion we can´t use an app in fullscreen mode and get the another display free for use.