Previous 1 2 3 4 Next 45 Replies Latest reply: Nov 27, 2012 12:01 PM by Eric Root Go to original post
  • p-smyth Level 1 Level 1



    Bluetooth seems to be problem and people have got around this by only turning on bluetooth devices after booting. I definitely had a problem with the anti-virus software too though.

  • Tjaka Level 1 Level 1



    Can you also tell how to to turn off bluetooth devices during booting?


    After you have posted this, I am going to test this and will reply here.

  • p-smyth Level 1 Level 1

    Don't turn them on to begin. I mean the mouse and keyboard.

  • Tjaka Level 1 Level 1

    Ok, is it that easy?!


    I was already looking for some startup files...


    Thank you very much for your reply!

  • p-smyth Level 1 Level 1

    It's a quick fix, but yes.


    Funnily, I had a similiar problem with another iMac (late 2011) booting in safe mode in Lion which I also corrected by not turning on the bluetooth devices before it was fully booted. This was properly solved by a recent firmware update, so I would hope that something similar will be done for Mountain Lion and my older iMac soon.

  • IRON BLUE Level 1 Level 1

    I had the exact same problem.


    If you use a wireless keyboard and mouse leave them on all the time don't switch them off when you shutdown.


    This will probably solve the issue until a fix comes out.

  • Tjaka Level 1 Level 1

    Unfortunately, for me that did not help...

  • Ovilnie Level 1 Level 1



    I also have the same problem as reported here in my Mac Mini (Early 2009). It  was not fixed with three different ML updates (the last a clean installation), or with varied suggestions here and in other forums (reset PRAM, safe mode, Bluetooth...).


    Waiting for an update that fixes it!  

  • vonundzu Level 1 Level 1

    I just installed the 10.8.1 update and it does not fix this issue! Sad but true... (maybe in 10.8.2 ?) But: If I turn off bluetooth before I turn off my MacBook Pro (5.1) it will boot normally next time.


  • seamuswarren Level 1 Level 1

    Someone posted the issue goes away if you don't turn on your connected Blutooth devices (keyboard & mouse) before boot up. I think you can turn on the Blutooth devices when the grey screen pops up because this is after the initial "Power On Self Check" or whatever it's called.


    I was having this "Black Screen of Death"... well, not really "Death" but it was annoying haveing to type "exit" from what looked like a DOS screen on a Mac.


    I was having other issues with Internet connectivity too. Could connect to the wifi easily enough but the internet connection would hang after a little while. Could not access Software Update or any web locations via Safari. I had to SMC, PRAM though a simple Restart would work some of the time. It was as if the some conflicting module would load at some point causing the Internet connectivity to hang.


    I had been messing around with my Users directory while moving it to an external disk array so I errased "Macintosh HD" and installed OS Mountain Lion again from scratch - a clean installation.


    After this clean installation I was still having the problem of the Internet hanging until I hooked up the Netgear Gateway to an Apple Time Capsule, wich seems to have stabilised the connectivity somewhat. I intend to connect the AppleTV and any other networked devices to this Time Capsule Hub and use it's 1TB internal drive with Time Machine if I decide I don't mind plugging in an additional exteral drive like a Seagate GoFlex.


    Anyway, I'm using an early 2009 iMac and the Single Boot (black "DOS-like" screen) and WAN instability seem to have been eliminated... for now.

  • alexcaplin Level 1 Level 1


    I have an late 2009 iMac and I recenlty downloaded Mountain Lion and I'm also getting a start up error message !

    Looks just like the picture that the person took.Hope they fix the issue soon.When I first saw it I did a double take and thought this reminds me when I had an HP pc and running windows vista ouch !

  • vonundzu Level 1 Level 1

    I now also have this issue when bluetooth is turned off, just like most of you...

  • Daelliott Level 1 Level 1

    Yep, same problem. Late 2009 iMac now starts up with the black screen,

  • alexcaplin Level 1 Level 1

    well the problem disapeared until today when I installed the latest mountain lion update. Now it's back the nice black screen !