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Can't install Snow Leopard - Macintosh HD cannot be used to start up your computer

Discussion in 'OS X' started by Gray Tragedy, Aug 7, 2010.

  1. macrumors newbie


    I'm trying to install Snow Leopard, but when I put in the installation disk and try to install, I'm quickly stopped from installing when I get to the screen that says "Select the disk where you want to install Mac OS X." The only option is "Macintosh HD," but there is a yellow triangle on it and when I click on it, it says "Mac OS X cannot be installed on 'Macintosh HD,' because this disk cannot be used to start up your computer."

    I do also have Ubuntu running on my computer. I'm attaching a screenshot of Disk Utility so you can see how my hard drive is partitioned.

    I don't really understand why it can't be installed there -- Mac OS X is the disk that starts up when my computer starts. I was researching a bit and found it might be a problem with the partition scheme -- but if it is I don't know how to rectify that or know where to go from there.

    Ideally I do not want to have to reformat my hard drive or install Mac OS X from scratch, as I will then have to re-install Ubuntu as well.

    Can anyone help me out? Thanks!

    Attached Files:

  2. macrumors 6502

    You can check your partition scheme by selecting your top-level drive in the left sidebar, and looking under Partition Scheme at the bottom.

    Solutions can be found in this support article.
  3. macrumors newbie

    It's GUID, which I believe is what it's supposed to be, right?
  4. macrumors 6502

    Yes, that is what it's supposed to be.

    I have installed Ubuntu in the past, and trying to uninstall it practically erased my Mac (thankfully, I had a backup). The solution turned out to be changing the partition scheme back to GUID, but I did have to reinstall OS X.

    I'm not entirely sure where to go from here. My guess is it's a conflict from installing Ubuntu.
  5. macrumors 6502

    I'm curious as to why your Macintosh HD is nearly full. I don't think 9GB is enough space to install Snow Leopard, but that should give a different error message.
  6. macrumors newbie

    According to Apple you only need 5GB. And, as you said, I'm sure it would tell me if there weren't enough space.

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