Apple says that Mountain Lion is compatible with a handful of Mac Models, including 2007 iMacs and later, the late-2008 aluminum MacBooks and the 2009 MacBooks, all MacBook Pros that debuted after 2007, as well as MacBook Airs and Mac Pros after 2008.
Apple has also made Mountain Lion compatible with 2009 Mac Mini models and later, as well as Xserve devices.
To find the exact model of your Mac by clicking the Apple icon in the top left corner of your computer screen, clicking "About This Mac," then clicking "More Info" on the bottom.
Adopters of OS X Mountain Lion will be disappointed to learn that a handful of apps, mostly from third-parties, won't work with the new Mac operating system. Apple Store employees may not know which applications are incompatible. To check out which of your favorite OS X and iOS applications will work with Mountain Lion (and Lion too), check out RoaringApps' full table of compatible and incompatible applications. There are literally thousands on this list, so it's best to use the search function to find which apps you need before upgrading to Mountain Lion.
A Sedated Mountain Lion
Submitter Diane Alexander owns a MacBook Air that's roughly a year and a half old. She said she had no issues running OS X Snow Leopard, but since updating her computer to Mountain Lion, she's witnessed considerable lag.
"When I close the computer for awhile and come back and open it, I get a white screen for a few seconds, and have to wait while it loads," Alexander wrote.
Submitter Jason Roberts, owner of a 2009 MacBook Pro, said that his computer is experiencing similar slowness. In fact, he's been frustrated with getting his computer to even turn on at times.
"Problems started right after the Mountain Lion install," Roberts said. "Almost everything I tried doing was insanely slow. I thought this was normal, because things were kind of slow with the Lion upgrade at first. Then streaming sites on Safari stopped working altogether, but worked with Firefox. My clock switched to a.m. instead of p.m. and I got the beach ball when I tried to fix it. My computer kept getting slower and giving more beach balls. Then finally everything that was open became unresponsive. System Preference[s] would not open. I had to try to restart by holding the power button. Only to be left without a functioning computer... All I have now is the grey apple screen with a frozen loading wheel."
Michael Schinis, a submitter to IBTimes, also said he's experienced similar speed issues with his mid-2011 MacBook Pro, noting that animations and even changing spaces show a significant amount of lag.
Natan Vigna, who owns a mid-2009 15-inch MacBook Pro with a 2.8 GHz Intel Core 2 Duo, said that OS X Mountain Lion is "painfully slow" on his machine.
"The only thing I see is the beach ball of death every two to five seconds," Vigna said in reference to Apple's loading icon. "I'm glad I only upgraded my toy laptop and not my real work machines that I use for work."
"The beach ball of death" was the center of another story of frustration with OS X Mountain Lion, submitted by IBTimes community member "kaboom."
"After downloading, accepting user agreements, installing, and rebooting, I get a white screen with a spinning 'loading' wheel. Normally this indicates that it's about to show me the login screen, however, this literally stayed on the screen for HOURS! I reluctantly rebooted only to find the same thing. I used Command-V to see what was getting hung up. 'bootcache.playlist...' was not loading or something like that. I then repaired permissions through the Disk Utility via Restore Mode, but it still didn't work. I did the "chmod -n -R /Volumes" thing and that didn't work. So, now I'm backing up my data before I get nuts and completely erase and start over."
Liam Vasey, an owner of a 2009 MacBook Pro with 8 GB of RAM and a SSD, has noticed display issues since upgrading to 10.8.
"Nothing works on hover," Vasey said. "The dock won't appear as I hover near the bottom of the screen, right click contextual menus don't work in the finder, button and link hovers on the web (any browser) don't work, basically anything I have to hover over with my mouse won't work now."
Gizmodo's Jesus Diaz discovered a few issues with his computer's speed, most interestingly while using Apple's latest laptop, the MacBook Pro with Retina Display.
"I used this computer for reviewing the final version of OS X 10.8 and, while it was perfect with Lion, the display is now very buggy," Diaz wrote.
"The zooming is often slow, the cursors sometimes disappear, some parts of the text fields don't refresh properly in Safari, animated GIFs get garbled frequently, and videos sometimes get distortions, especially if you try to rotate them in QuickTime Player. At times, there is also a perceptible slowdown, even while this is a fully loaded system with 16GB of RAM.
"Perhaps this is a problem unique to my computer, but I doubt it. None of these problems were present with the factory-installed OS X Lion. And this computer was almost virgin before the upgrade from Lion to Mountain Lion."
Submitter Robert King wrote in with an issue about burning multimedia through his optical drive on his 2008 unibody MacBook Pro. King said it "worked flawlessly the night before under Lion," but can no longer burn single or dual layer CD-R, CD-RW, DVD-R, DVD-RW.
IBTimes submitter Aubrey said she's noticed a bug within "Parental Controls" since upgrading to OS X Mountain Lion.
"Being fairly new to Mac when Lion came out, I was too chicken to upgrade, so last night, or perhaps this morning, I upgraded from Snow Leopard to Mountain Lion," Aubrey wrote. "Since doing so, my kids can no longer access YouTube on their account even if I go into System Preferences and "Always Allow" it. In fact, I can go under "Web" settings and lift all restrictions on websites, and they STILL can't access YouTube. I want to use Parental Controls, but right now it's not working as it's intended. Any ideas? I've called AppleCare, and after two hours of them finally sending me to a supervising agent and him taking over my computer and doing everything I'd already done and not quite seeming to understand why he got disconnected if I logged out even though I'd granted elevated permissions or whatever. They finally sent the problem to the escalation department."
Airplay Mirroring, one of the more touted features in OS X Mountain Lion was the center of the submission from IBTimes reader "Red Heron," who found that the service is still only half-baked.
"Airplay Mirroring is a slightly jerky when streaming video movies from Amazon even with a 30 mbs download service," Red Heron said. "It also will not work on MacBook Air models that are more than 18 months old."
IBTimes emailer Alison Dyson has been having issues with Mail since upgrading to OS X Mountain Lion.
"Our email keeps coming up with an error [that says it] cannot connect to the port," Dyson wrote. "If we close down Mail and reopen it works, [but] then about 30 minutes later it crashes again. Really annoying."
Rosi Bustamante, an IBTimes submitter, has also been having issues using Mail.
"I've also been having login password issues with Yahoo Mail," Bustamante wrote. "When I try to access my email using Sparrow, but it's also begun to affect it when I try to check my Yahoo Mail with my iPhone -- funny, not with my iPad! I also have not been able to compose in Yahoo Mail using Safari. Very bizarre."
IBTimes submitter "Chris" said Outlook is running slowly, but he's noticing a weird glitch in the application when running on OS X Mountain Lion.
"In Outlook, when composing an email, this sounds weird, but when I type 'I'd' or 'I'll,' the cursor jumps to another window causing me to have to mouse click back on the email and type 'I would' or 'I will,'" Chris wrote. "I know it's weird, but it's there."
Shutting Down and Restarting
Mac Mini owners Peter and Ollie, both submitters to IBTimes, said they had issues shutting down their Mac Mini computers since updating to OS X Mountain Lion. Peter and Ollie said they reverted back to OS X Snow Leopard and Lion, respectively, since updating their systems, and they did not experience the issues of shutting down and restarting.
Reader Ronnie Yeoh said that his iMac is having a lot of trouble wrangling OS X Mountain Lion
"I CANNOT shut down my iMac (mid-2011) computer through the Apple logo," Yeoh said. "'About this Mac, Restart, Sleep, and Force Quit also does not work. I have to press the power button to shut down each time. This is bad."
OS X Mountain Lion Fixes and Solutions
"Just did the upgrade on a near-new MacBook Pro with 8 GB and a Hybrid Drive (8GB NAND)," said "Tony from OZ," an IBTimes submitter. "Mine was taking ages to start and shut down and, on a few occasions, would not shut down at all. I reset SMC settings and cleared PRAM and it's back to its old screaming self again!"
Brett Reilly of Social Media SEO has five steps to diagnose all Mountain Lion erros, which involves verifying Disk Permissions with the Disk Utility and resetting the computer's PRAM, which often helps the installation. This comes straight from Apple:
"A small amount of your computer's memory, called "parameter random-access memory" or PRAM, stores certain settings in a location that Mac OS X can access quickly. The particular settings that are stored depend on your type of Mac and the types of devices connected to it. The settings include your designated startup disk, display resolution, speaker volume, and other information."
Reilly explains how to diagnose and fix issues in Mountain Lion on his page.
IBTimes submitter Jack Lichman updated his 2011 MacBook Pro to OS X Mountain Lion the morning it came out, and while installation was fine, he said the "computer did nothing but hang up, crash, and freeze." Lichman said it took him about "two hours to click on a browser, click my email bookmark, and read one email.
Lichman offered up a possible solution to users' similar lag issues.
"Once I cleared my PRAM, verified and repaired my permissions and the disk through the Disk Utility during start-up, my computer was running great. It still is. It's as fast or faster than Lion on normal computing. Only a couple of problems, it has added a few seconds to shut down and Time Machine seems to take a little longer to back up. Besides that, it works like a dream."
Some users may discover that after upgrading to OS X Mountain Lion that some of their old files and applications have gone missing. Of course, this is always an infuriating moment for Mac users, when they can't find what they're looking for after a major software release.
Not to fear: Apple was ready for this issue: Mountain Lion automatically identifies the applications and documents that won't work on the new OS and places them in a folder in your Finder, appropriately named "Incompatible Software."
Apple will likely issue solutions to some of these bugs in the system, but some users are finding ways to get their computers up and running after an initial stumble with OS X Mountain Lion.
To any Mac users experiencing any issues, errors or bugs with Mountain Lion, please feel free to write in or leave a comment at the bottom of the page. If you have solutions to any of these issues, please, help out your fellow reader! Be sure to note which kind of Mac (model, year) you own.
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