When the clone is completed you have a fully bootable installer that you can use without having to re-download Mountain/Lion. Double-check you got it right, then click on the Restore button. Drag the mounted disc icon from the Desktop into the Source entry field. Select the USB flash drive volume from the left side list and drag it to the Destination entry field.į. Click on the Restore tab in the DU main window.Į. Select the USB flash drive from the left side list.ĭ. Double-click on the InstallESD.dmg file to mount it on your Desktop.Ĭ. You are going to clone the content of the InstallESD.dmg disc image to the flash drive as follows:Ī. Plug in your freshly prepared USB flash drive. In this folder you will see a disc image named InstallESD.dmg.Ĥ. Double-click on the SharedSupport folder. Double-click on the Contents folder to open it. CTRL- or RIGHT-click on the installer and select Show Package Contents from the contextual menu. Locate the saved Mountain/Lion installer in your Downloads folder. The format process can take up to an hour depending upon the flashģ. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, check theīutton for Zero Data and click on OK to return to the Erase window.į. Click on the Erase tab in the DU main window.Į. Select the volume you just created (this is the sub-entry under the drive entry) from the left side Click on the Partition button and wait untilĭ. Partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, set the Under the Volume Scheme heading set the number of partitions from the drop down menu to one.

Click on the Partition tab in the DU main window.Ĭ. After DU loads select your flash drive (this is the entry with the mfgr.'s ID and size) from the left Open Disk Utility in your Utilities folder.ī. Get a USB flash drive that is at least 8 GBs. Go to your Applications folder and make a copy of the Mountain/Lion installer. After Mountain/Lion downloads DO NOT click on the Install button.

After downloading Mountain/Lion you must first save the Install Mac OS X Mountain/ If you download your own 2nd copy then you can make a bootable installation flash drive:ġ. See OS X (Lion/Mountain Lion)- About OS X Recovery. Rather it is through Internet Recovery should it be required. Apple does not supply a freely downloadable copy via the App Store. If you want a separate copy of Mountain Lion, then you will have to purchase and download it.

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