How To Prepare Your Mac For Mountain Lion

How To Prepare Your Mac For Mountain Lion

Mountain Lion, Apple’s next version of Mac OS X (10.8), is due any day now (with the latest rumours pointing to a July 25 release date). This means now is the perfect time to prepare your Mac for the smoothest upgrade transition.When Mountain Lion becomes available, you’ll be able to download and install it from the Mac App Store for $20.99 and get it up and running in about 30 minutes. However, operating system upgrades aren’t always so simple, so doing a few maintenance tasks beforehand can save you frustration later.

Before You Upgrade, Part 1: Find Out If Your Mac And Apps Are Compatible With Mountain Lion

Before you even think about getting all those new features in Mountain Lion (such as the new Messages app, AirPlay Mirroring and updates while your MacBook takes a “Power Nap”), you need to know if your computer meets the minimum system requirements. Most Macs sold in the last few years qualify, but Apple has tightened its requirements for this OS upgrade. Some older Macs — even ones that qualified for Lion — won’t make the cut for Mountain Lion.

The general system requirements are straightforward:

  • OS X v10.6.8 or later
  • 2GB of memory
  • 8GB of available space

Apple also lists which models support Mountain Lion:

  • iMac (Mid 2007 or newer)
  • MacBook (Late 2008 aluminium, or Early 2009 or newer)
  • MacBook Pro (Mid/Late 2007 or newer)
  • Xserve (Early 2009)
  • MacBook Air (Late 2008 or newer)
  • Mac mini (Early 2009 or newer)
  • Mac Pro (Early 2008 or newer)

Some new features, such as AirPlay Mirroring, require newer machines sold in the last year.


To find out if your Mac qualifies, click on the Apple in your menubar, then “About this Mac” and hit the “More Info…” button. The About this Mac summary window will show your model and release date, as well as the amount of memory installed. (Click the Storage tab to see if you have enough free space.)

One special note for Hackintosh people: check Tonymac’s blog post on getting ready for Mountain Lion for notes about additional requirements or potential issues.

If you have a Mountain Lion-compatible system, continue on. (If not, you could either think about upgrading your system or not worry about it — your version of OS X will continue to run just as fine as before, and Apple will still support it with occasional security updates.)

Check if your apps are Mountain Lion-compatible

You’ll also want to do a quick check to see if your favourite apps are compatible with the new OS. You can check individual softwares’ websites to find out if the developers are planning to support Mountain Lion or go to RoaringApps for a broad list of compatible (and incompatible) apps. The list is growing and ongoing though, so if your app currently has an incompatible status, keep in mind that most apps will eventually update to support Mountain Lion.

Before You Upgrade, Part 2: Clean Up And Optimise Your Hard Drive


Mountain Lion only requires 8GB of disk space, but even if you’re not running out of room on your hard drive, it’s a good idea to clear your Mac of all the useless applications, temporary files and other space wasters so you don’t carry them over to your new setup.

Our guide to speeding up, cleaning up and reviving your Mac walks you through uninstalling apps you don’t use and freeing up disk space. In short, here are the tools recommended for the task:

  • Remove apps you no longer need: AppCleaner (free) — our favourite app uninstaller for the Mac — lets you simply drag and drop apps to completely delete them
  • See which files are taking up all that space: Disk Inventory X (free) maps your hard drive usage into “treemaps” or DaisyDisk ($US9.99) not only offers gorgeous disk usage visualisations but also lets you directly delete the big space wasters.
  • Run disk maintenance utilities: OS X’s built-in Disk Utility can make sure your hard drive is error-free. Head to Applications > Utilities > Disk Utility to verify and repair disk permissions and the disk itself.

For ongoing system maintenance, consider using a system optimisation utility, such as our favourite Mac system tweaker, OnyX (the developers note that OnyX for Mountain Lion is in development now).[clear]

Before You Upgrade, Part 3: Back Up Your Mac


Actually, don’t just backup your Mac — test that backup too. Backing up your Mac with OS X’s built-in Time Machine is really easy: plug in an external drive and turn Time Machine on. Test the backups by doing a few restores of older and newer files to make sure you can recover your files if needed.

Optionally, you can clone your entire drive using our favourite tool for the job, Carbon Copy Cloner, so you can restore the whole system if necessary.[clear]

Before You Upgrade, Part 4: Run System And Third-Party Software Updates


Regularly performing software updates is one of the few basic maintenance tasks you need to do for your Mac, and it’s especially important before an OS update. Run the system updates by going to the Apple menu > Software Update.

At the very least, if you’re running Snow Leopard (OS X 10.6), make sure you run Software Update so you’re on the latest, minimum OS version, 10.6.8.

Before You Upgrade, Part 5: Organise Your iCloud-Related Files


Finally, while you’re at it, now is also a good time to clean up your address book, calendars, photos and other files that will be synced to Apple’s iCloud online storage service. (Find out which services you have set up for iCloud syncing by going to System Preferences > iCloud.) This isn’t really necessary for installing Mountain Lion, but the new OS places much more emphasis on iCloud storage for saving application settings and keeping your documents synced. You can get ahead of the game by weeding out the iCloud-related files you don’t need so they don’t take up more space than the 5GB free allotted.

We’ll be covering Mountain Lion in depth once it’s released, including alternate install methods, how to get the most out of the new operating system, and even whether or not you should actually upgrade. But for now, take the opportunity to get your system freshened up and ready for Mountain Lion.


  • I have to say this again, I thought Macs were supposed to “just work”? Seems like a lot of work for what amounts to a service pack/point upgrade…

    • Honestly, I’m just gonna get my upgrade, install it and move on, and it’s probably going to “just work” (just as every other upgrade has). LH is just suggesting a bit of spring cleaning before you do.

    • I know people who’ll just install over the top of Lion, and it’ll most likely work fine, and I know people who’ll follow this list religiously. I sit somewhere in the middle. My preference is to make a Mountain Lion boot disc, as I did with Lion, and install off the CD.

      Ensuring that apps are compatible and are up to date is just good practice – it’s not really fair to include this point into the argument that “mac’s are supposed to just work”

      The other tips are really just good maintenance tips , and if you don’t do them on a semi-regular basis, at least doing them before an OS upgrade is probably a good idea. I know users who never do any of these things, and their macs still work, they’re just not running in optimal condition. It’s not going to play a huge factor in the success of the OS install, but it’ll ensure that you’re backed up, and that you have a system running as smooth as possible. It may also eliminate (or at least make users aware of) the potential risk to your productivity if you rely on an app that’s not supported by ML.

      All of these general maintenance tips are applicable to windows users as well.

    • I installed Lion straight over the top of Snow Leopard and it “just worked” I think this is more for the people that enjoy their technology and want to go the extra mile.

    • You don’t have to upgrade as it works pout of the box just fine but as we are all keen to have the new features – well it is better to be prepared than sorry.

      Have you tried to upgrade a Windows OS recently – you better format you HDD and start from scratch?

      • Yes. Any PC 2.5″ SSD will work, but I believe the ones from support TRIM natively in OSX (happy to be wrong though).

        Don’t bother with the 6G ones; your laptop only has a 3G SATA port.

          • Very easy to do – I can’t remember if yours was the MBP with the accessible battery or just the straight out flat bottom – either of them are very easy to do, but you’ll need a T6 torx screwdriver to swap the screws out of the HDD to the SSD. But yes – as Karthik has said, macsales have videos 🙂

  • I have a Mid-2007 iMac with 2GB of RAM (just made it!), but can anyone who has used the GM tell me if it’s speedier/slower/similar to Lion?
    It’s not running as fast as it used to and Lion was a stretch, just wondering if it would be stretching it further to get Mountain Lion.

  • I installed Lion over Snow Leopard, then backed up to time machine and transferred to new SSD a few months later. Pretty sure its those old plist files causing my PRAM to wig out constantly and my machine fails to boot without resetting PRAM almost every time.

    Moral of the story is FRESH INSTALL FTW!!
    (Pity that Apple force us to do annoying unpacking of the app just to create an install USB, this should be easier for non power users)

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