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iMac freezing after Mountain Lion Upgrade

17189 Views 54 Replies Latest reply: Dec 1, 2012 1:41 PM by Arosebud0 RSS Branched to a new discussion.
  • cosmofromwatertown Level 1 Level 1 (0 points)
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    Aug 23, 2012 2:29 PM (in response to cosmofromwatertown)

    I updated Firefox (also applied OSX 10.8.1 update). When I restarted Firefox a warning came up stating that Microsoft Silverlight has created known instabilities and vulnerabilities in systems, and it automatically turned it off (at least in Firefox).


    Since then I've begun turning off plugins in both Firefox and Safari. You have to remove Silverlight manually in Library/Internet Plugins/ and also in Library/receipts/. I might be imagining it, but I think I'm seeing more stability.

  • Grahber Calculating status...
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    Aug 24, 2012 2:58 AM (in response to SteamPunk)

    Mine too, my curser opens everything as it passes over, everything freezes, I thought I had a virus but my mac keeper tells me not...when I can get in that is.    I can hardly use my mac at all.   The only change I have made recently is to download and install mountain lion.    Sent a bug fix to apple but no response, so now having to use my PC laptop for any major stuff. IPhone & iPad for day to day.  I'm stumped

  • jeunic Calculating status...
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    Aug 31, 2012 8:36 AM (in response to vsserafim)

    I have a 2010 IMac and since upgrading to Mountain lion, iphoto and itunes constantly freeze and I get non responding in force quit! I have lost photos from past year in iphoto and music not appearing in itunes! At a loss for what to do at this point! My iphone isn't syncing what i say to sync in itunes. PLEASE Fix apple!! I usually wait to upgrade to new system but thought this one was out longer than it was. Regretting now!!!

  • PopIsBros Calculating status...
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    Aug 31, 2012 8:40 AM (in response to vsserafim)

    I had the same problem on a macbook Pro bought in 2010.

    I have made a full fresh reinstall from scratch of Mountain Lion and problem is gone...


    A bit rude, but it works.

  • BaldBrain Calculating status...
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    Sep 3, 2012 8:08 AM (in response to vsserafim)

    I'm having what sounds like the same problem on my 24" early 2009 iMac.  Started happening after I upgraded to 10.8.  Screen flickers, sometimes distorts, then completely freezes.  I can still move my mouse but can't interact with anything on the screen. I have to do a hard reboot which makes me nervous every time.  It has occured immediately after waking from the screen saver, other times just a few minutes after I turn the iMac on. 

  • cosmofromwatertown Level 1 Level 1 (0 points)
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    Sep 3, 2012 8:55 AM (in response to vsserafim)

    I think the main culprit is non-stock screen savers that don't play nice with the OS. I've had a lot of the problems go away (not all) by switching to an Apple written screen saver such as Flurry. For some reason not everything comes out of the new sleep routine once activated. I've noticed this first by clicking on Mission Control and finding that it is usually stuck also. Others have had some luck also by switching screen savers.

  • blindnet Calculating status...

    Same problem here, I also thought it was related to a 3rd party screen saver, but now flickering occurs any time now, not only when the screen saver is running.

  • cosmofromwatertown Level 1 Level 1 (0 points)
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    Sep 3, 2012 5:22 PM (in response to vsserafim)

    While nuking your OS may have helped you, it has not helped everybody. Apple designs the OS to work, but they can't always know what every combination of 3rd party software that each machine might have installed. Especially ones that run in the background. Therefore, it is very reasonable to turn these off, it has helped me.


    I would ask your patience. If not, you could always click 'this solved my problem' and end the discussion. While the discussion may have begun with you, your's is not the only concern. Different problems can have similar symptoms.

  • bestraider Calculating status...
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    Sep 5, 2012 11:12 AM (in response to vsserafim)

    From Italy - HELP

    I had the sequence of problems on my i7 purchased in June. after 5 phone calls with apple, my mac turns off after 5 seconds ...... are very .... tired and worried

  • Grahber Level 1 Level 1 (5 points)
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    Sep 17, 2012 3:06 AM (in response to vsserafim)

    Following a visit to the apple store, where they checked my iMac for me it has transpired that my issue appears to be the fault of my TrackPad malfunctioning!  After all that!!

  • slbyard Level 1 Level 1 (5 points)
    Currently Being Moderated
    Sep 28, 2012 11:52 AM (in response to vsserafim)

    My 27" iMac is doing the same thing! Only after Mountain Lion.


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