Incompatible software warning: If you upgraded a Snow Leopard or Lion Mac, the first time you boot into Mountain Lion you may see a dialog box informing you that some of the existing software on your Mac is incompatible with the new OS, and listing that software. (Apple provides more information about such software in a support article.) You’ll usually see this message if you had kernel extensions—low-level software that patches the operating system itself—installed under Snow Leopard or Lion that Apple specifically knows won’t work with Mountain Lion. It’s also possible to see the incompatible-software dialog box if you installed Mountain Lion onto a blank drive and then transferred data from another Mac or drive, but it’s less likely—OS X’s Migration Assistant generally doesn’t import kernel extensions and similar software responsible for low-level processes. In either case, OS X automatically moves this incompatible software to a folder called Incompatible Software at the root level of your startup drive.
Once you’re up and running in Mountain Lion, you’re almost done. You may find, despite your pre-installation checks, that some of your existing software needs updates. Similarly, if you’ve performed a “clean” install of Mountain Lion (onto a blank drive without transferring accounts and data), you’ll need to spend a bit of time setting things up, and you'll want to reinstall all your favorite apps.
Check (again) for updates: The first thing you’ll want to do is choose Software Update (from the Apple menu) to open the Mac App Store app and install any pending OS updates. If you’ve installed Mountain Lion in the first few days of availability, chances are you won’t have any (especially if you checked for updates to Lion or Snow Leopard immediately before upgrading, so you already have the latest updates to other Apple software), but it can’t hurt to be sure. And if you’ve waited a week or more to install Mountain Lion, there’s a good chance Apple will have released a minor update—or will sometime soon.
Even if no updates to Mountain Lion itself are available, you may find that, after installing OS X 10.8, a firmware update is available for your Mac. For example, some Mac laptops require a firmware update to support Mountain Lion’s new Power Nap feature, and this firmware update will appeared only after installing Mountain Lion, presumably because it’s not necessary under Lion or Snow Leopard.
Set up printers, if necessary: If you didn’t upgrade from an already-configured installation of Lion or Snow Leopard, you’ll want to set up your printer(s). As with Snow Leopard and Lion, Mountain Lion doesn’t include many printer drivers; rather, when you set up a printer, the OS determines which drivers you need and, if necessary, either downloads them automatically or helps you get them. Open the Print & Scan pane of System Preferences and click the Add (+) button, and you’ll see a list of connected and nearby (Bonjour) printers. Choose one, and OS X will see if drivers are available. In the case of my Brother 7820N, the bottom of the Add window displayed the message “The selected printer software is available from Apple. Click Add to download it and add this printer.” I clicked Add and, sure enough, OS X proceeded to download the software and set up the printer.
Check for incompatible software and, if necessary, install apps: Next, if you saw the aforementioned incompatible-software dialog, now’s a good time to check the contents of the Incompatible Software folder at the root level of your startup drive, and then check each vendor’s website for updated versions of that software. Similarly, if you performed a clean install—installed Mountain Lion onto a blank drive and didn’t transfer accounts, applications, and data—it's time to reinstall your app. Just be sure you've got the latest versions, as well as any updates you'll need to apply to software you install from CDs and DVDs.
One compatibility issue of note is that if you upgraded from Lion or Snow Leopard and you had Adobe’s Flash Player 10.3 or later installed, it will work fine after upgrading; however, if you had a version prior to 10.3 installed, Flash will be removed and you’ll be instructed to download the latest version. (Thanks to Macworld contributor Joe Kissell for this tip.)
Note that the first time you try to load a webpage or run an app that requires Java, Mountain Lion will prompt you to download and install the Java runtime, even if you upgraded from Snow Leopard or Lion and you’d previously installed Java. This is normal—you shouldn’t worry that installing Mountain Lion somehow “lost” any of your data or apps.
Enable FileVault: If you want to use FileVault, OS X’s disk-encryption feature, but it’s not enabled—either because you’ve never used it or because you upgraded from Snow Leopard and followed my advice to disable it before upgrading—now’s the time to turn it on, via the Security pane of System Preferences. Note that if the Mountain Lion installer (or the Lion installer before it) was not able to create a Recovery HD partition on your drive, you won't be able to enable FileVault.
Check services: On several Macs—but not all—I upgraded from Lion to Mountain Lion, the first time I logged in to the new OS, I was alerted that Location Services and Sharing services had been disabled. You may or may not see these messages, but it’s a good idea to take a quick look at the Sharing pane of System Preferences, as well as the Privacy tab of the Security pane. If any of these services have been disabled, and you want to use them, turn them on now.
Upgrade and installation challenges
For most people, Mountain Lion—like Lion before it—is easy enough to get and easy to install. But, also as with Lion, upgrading to OS X 10.8 presents challenges for a few groups of people.
People with Mountain Lion-compatible Macs who are still using Leopard (OS X 10.5): There are a few Mac models that originally shipped with OS X 10.5 and are compatible with Mountain Lion. While I’m certain there are a good number still running Leopard, I’ll bet few of their owners will want to make the jump directly from Leopard to Mountain Lion—if someone has been happy enough running 10.5 for three or four years that they never bothered to install OS X 10.6 or 10.7, I doubt they’ll be running out to install 10.8.
That said, one if you’re one of the people who really do want to jump directly from 10.5 to 10.8? Apple’s official policy is that you need you purchase and install Snow Leopard ($29 for a single copy or $49 for a family pack) and then upgrade to Mountain Lion, bringing the cost of upgrading to either $49 or $69, rather than $20.
The Mountain Lion installer, like the Lion installer, is strict about requiring OS X 10.6.8. The installer application itself will launch under Leopard, but it won’t let you install Mountain Lion, either over Leopard or onto a bare drive. Nor can you mount a Leopard drive on a Mac running Snow Leopard, Lion, or Mountain Lion and then install 10.8—the installer simply refuses to install over Leopard.
But what if you own a copy of Snow Leopard for the Mac in question, but you don’t want to add an hour or two to the installation process by installing Snow Leopard first? I’ve upgraded my article on installing Lion over Leopard to also cover Mountain Lion. It’s not a simple procedure, but it works.
People with slow or limited-bandwidth Internet connections: If your Internet connection is slow, it will take a long time—perhaps days—to download the 4GB+ Mountain Lion installer. Even worse, if your ISP enforces caps on your Internet-data usage, you could end up paying a hefty price for the privilege.
If you’ve got a Mac laptop, you can instead tote it to your favorite Apple retailer, the library, a friend’s house, or the office—anywhere with a fast Internet connection—and download the Mountain Lion installer there. In fact, when Lion was released, Apple’s official policy was to invite you to your local Apple Store and use the store’s Internet connection to download Lion; store employees would even walk you through the purchase, download, and installation processes. I suspect that will continue to be the case with Mountain Lion.
Of course, if your Mac doesn’t happen to be portable, or if you live in an area where you can’t borrow a fast, cheap Internet connection, you'll need to find another solution. If you’ve got an Apple Store nearby, you may be able to take a portable hard drive or an 8GB-or-larger thumb drive to the store and ask to purchase and download the installer on one of the store’s Macs; similarly, you could borrow a friend’s computer, or—if you’re lucky enough to have a Mac at the office—use your work computer to download Mountain Lion.
Last year, Apple made available a $69 bootable flash drive containing the Lion installer; the company hasn’t yet announced if it will do the same for Mountain Lion. I’ll update this article with the latest information as it becomes available.
Businesses, schools, and other organizations and institutions that need to install Mountain Lion on many different computers: When Lion was released last year, we heard concerns from large installations—schools, businesses, and the like—about the Mac App Store-only distribution. These organizations often need to roll out new versions of OS X to many Macs, and forcing each user to download and install Lion presented significant technical, logistical, and support issues. OS X 10.8 presents the same challenges. With Lion, Apple released a document titled OS X Lion for Business and Education that explained the options for these organizations. The company hasn’t yet released a version for Mountain Lion, but I’m assuming the options will remain the same: While organizations will use the same purchasing procedure as always to buy OS X, they’ll be given one Mountain Lion redemption code for each purchase contract. After using that code to download the Mountain Lion installer from the Mac App Store, that copy of the installer can be used on any and all Macs covered by the contract.
To do so, Apple says customers can copy the Mountain Lion installer to the
/Applications folder on each Mac and then run the installer from there, or they can create a NetInstall or NetRestore image, or use Apple Remote Desktop. They can also create one or more bootable Mountain Lion-install drives and then install the OS using those.
While researching this series of articles, I installed literally dozens of copies of OS X 10.8 on a variety of Mac. As with Lion, my experience has been that for the typical Mac user with a broadband connection, the process of purchasing, obtaining, and installing Mountain Lion is easy and relatively pain-free. Still, heeding the advice above will reduce the chances of problems and make the upgrade go as smoothly as possible. Once you’re up and running, check out all our articles about the new OS, which cover its features, built-in apps, and more.
(For an even more in-depth look at upgrading to Mountain Lion, check out Macworld contributor Joe Kissell’s Take Control of Upgrading to Mountain Lion, which covers such topics as extensive pre-install diagnostics, clean installs, installation troubleshooting, and much more. And see our complete installation guide for how-tos on using OS X Recovery, creating a bootable install drive, performing a clean install, and installing Mountain Lion over Leopard.)
[Dan Frakes is a Macworld senior editor. His Macs are all very tired from having Mountain Lion installed on them over and over and over and over.]
Updated at 8:30am to reflect Apple’s updated purchase dates for the OS X Mountain Lion Up-to-Date Program