Apple has just released the Mac OS X 10.8 Mountain Lion and I’m sure many of you who own multiple Mac computers will be worrying about purchasing multiple licenses of Mountain Lion in order to install it on all your computers. Well, don’t fret. The personal use license which came into effect from Mac OS X 10.7 Lion, permits users to purchase once and install the OS on all their computers authorized for personal use. So how to go about it? If you have a good broadband internet & don’t have to worry about the bandwidth, then you can open the Mac App Store on your other Macs, go to Purchases tab and you can re-download Mac OS X Mountain Lion on each of your computers. For others, below are couple of options.
Install or Upgrade OS X Mountain Lion on More than One Computer
Method 1: File Sharing over the network
This is the simplest of the 2 methods we have. Assuming that you have both (or all) your Mac(s) on the same network, you can simply enable File Sharing to copy the installable.
Download Mac OS X 10.8 Mountain Lion from Mac App Store. Do NOT install it yet. This is because, Mac OS will delete the installer once the installation is complete. On the source Mac, launch System Preferences and click on Sharing. Enable File Sharing by clicking on the checkbox next to it. Close System Preferences. Go to your Applications folder and look for “Install OS X Mountain Lion.app“ Press Command+K to Connect to server and then click on Browse to find the other shared Macs. Now on your shared Mac, navigate to Applications folder, and drag & drop the Install Mac OS X.app file. Once the file is copied, launch the installer to upgrade to Mountain Lion.
In case your Macs are not on the same network, check out the alternate method.
Method 2: Copying to External Storage
This method involves copying the Mountain Lion installable onto an external storage device like a USB stick or a DVD drive. Mind you, the OS X 10.8 installable is almost 4.05GB, so you need to have a storage bigger than that (at-least 4.25GB).
On the Source Mac, open Applications folder and look for “Install OS X Mountain Lion.app“ Plug in your external storage device and copy/burn the installable onto it. Disconnect the external storage from the source Mac and plug it into the recipient Mac. Copy the “Install OS X Mountain Lion.app” onto the Applications folder of this Mac. Launch the installer and upgrade to Mac OS X Mountain Lion.