Make a bootable image copy of OSX 10.8 Mountain Lion after downloading the App from the store but before installing on your drive. Copy the image to a local drive or make a bootable external disk or DVD.

Install Mac Os X Mountain Lion.app Download Free

After downloading the Mountain Lion.App from the store aka “Install Mac OS X Mountain Lion”, find it in the /Applications directory, control click it to bring up a contextual menu and select “Show Package Contents” from the menu.

show package contents

Official OS X Lion.app Installer from the Mac App Store.This is version 10.7.0 (release). To update to 10.7.5 please visit the combo update link from Apple. Download Mountain Lion for Mac. OS X 10.8 Mountain Lion is Apple's latest operating system for Mac. It brings OS X much closer to iOS in terms of features and syncing with iPads and iPhones. We've already given you a lowdown on the most important changes in Mountain Lion most of which are features taken from iOS.

Official OS X Mountain Lion.app Installer from the Mac App Store. Both versions 10.8.4 AND 10.8.5 full installers included (zipped). Un-archive the zip archive and you will get the app Installer. A bootable ISO or bootable USB can be made directly from the InstallESD.dmg disk image found under Contents/SharedSupport/. These are iClarified instructions on how to install OS X Mountain Lion 10.8 from the Mac App Store.You can find more detailed instructions in the text versio. Mountain Lion is the latest OS X which is available to purchase and has access to download from the App Store. Mountain Lion is available in the format of digital download in the Mac App Store and not available on a disc.

Install Mac Os X Mountain Lion App Download

This brings up a Contents folder, from here navigate to Contents/Shared Support/InstallESD.dmg, and thats the disk image to burn, it contains all the goodies.

Double click it, you can skip the verifying process, then the disk image mounts as a volume in the sidebar.

Image to Bootable DVD

Select the mounted volume in the sidebar then either click on the burn icon if you have it set up or choose the option from the File menu, pop in a blank DVD and thats a job done.

make-a-bootable-mountain-lion-image

You can also use /Utilities/Disk Utility to do the same thing, just launch Disk Utility, highlight the InstallESD.dmg and burn.

Copy to Local Drive

Install Mac Os X Mountain Lion App Store

To keep a separate image of the dmg, option drag a copy to your desktop, this will make a copy of the InstallESD.dmg leaving the original Lion app intact.

Image to a Bootable External Disk

To make a bootable image to a drive instead of a disk, you need to do a restore in Disk Utility, select the InstallESD.dmg as the source and the disk volume as the destination. Enusure that the destination volume is correctly formatted as HFS+ Extended Journaled. Click “Restore”.

Install Mac Os X Mountain Lion.app

If you haven’t got the Mountain Lion App to start with and can’t re-download it from the App store, you can still make a partial boot drive from the hidden Recovery Partition, check it out.