This makes it easier and more convenient to upgrade your OS than having to buy and use a DVD or thumb drive, but it also raises a number of questions, and it presents upgrade obstacles for some users. More specifically, it’s available only as a download from Apple’s Mac App Store. OS X 10.8-better known as Mountain Lion-inherits Lion’s distribution method. But Lion changed all that by making OS X available for direct download. – I have confirmed this working on a Macbook Air 11″, 2010, 1.6Ghz version.Before Lion (OS X 10.7) debuted last year, installing the latest major version of Mac OS X meant buying a disc and slipping it into your Mac’s optical drive. – I would recommend creating a separate partition for your OS X Lion installation as well.Hold Option/Alt after your see the Apple logo appear and boot with the thumbdrive in your Mac.Ĭhoose the USB Drive to install OS X Lion from your USB Thumbdrive! Once its finished, you now have a bootable OS X Lion install thumbdrive (basically just like what the Macbook Air ships with).ĥ.

I recommend erasing the destination, so be sure to backup any data on the thumbdrive prior to this step! This will take a few minutes to do. (ie THUMBDRIVE in the screenshot) and then click Restore Once you have it chosen, click and drag your USB Thumbdrive from the left pane to the Destination box. Click on the Browse button and locate the. On the right pane, go to the Restore tab.ģ. This is very handy for us Macbook Air users that do not have an external optical drive.ġ.

We can then boot the USB Drive on our Mac to install OS X Lion from it. dmg installer file for OS X Lion onto a usb thumbdrive.

– USB Thumbdrive or Memorycard Reader w/memory card (4GB mininum, data will be destroyed).

– Mac running OS X Leopard or Snow Leopard.

– OS X Lion installation DMG (hint: file named: mac_os_x_10_7_11a390.dmg).

We will need a copy of the installer dmg (not provided) and a 4GB USB Thumbdrive or Memorycard Reader w/memory card and a Mac to convert the dmg to a bootable usb thumb drive. This recipe will explain how to make a USB Thumb Drive bootable with the OS X Lion Developer Preview installer on it and in turn allow you to install Lion on a Mac without an optical drive (ie Macbook Air line).

Mac os mountain lion usb installer