Windows and OSX wont boot afte partitioning

Discussion in 'Windows, Linux & Others on the Mac' started by Owencain, Sep 7, 2012.

  1. Owencain macrumors newbie

    Sep 7, 2012
    Hi so I have a 2012 MacBook pro, it is running mountain lion and I also boot camped it and installed windows 7. I partitioned the hard drives correctly and it has been running great. Today I was on windows and used the disk manager to shrink my windows partition so that I could create another seperate 5gb partition for school. After I did this, my computer was running fine until I restarted it. When the windows logo appears while booting, it freezes and it flashes a blue screen and then shuts down. When I hold down the option key to boot into Mac OSX, the only option that comes up is windows, not even my recovery disk.

    How do I fix this? I need to boot into these because all of my school things are on these drives. Please help
  2. murphychris macrumors 6502a

    Mar 19, 2012
    You can't use Windows utilities for resizing a dual-boot disk because it doesn't understand the unique and non-standard partition map Apple is using to make Windows on a Mac work. You have to use a 3rd party utility like CampTune (maybe Winclone can do it also).

    The easiest way to fix this is to blow away the disk and restore from backups. If you don't have backups, well this is the situation you're in right now that should convince you that it's a huge mistake to not have one. It's a vastly bigger mistake than using a Windows utility that cannot possibly have any idea that you have a Mac OS X volume on the disk or what to do with it when resizing.

    The not so easy way to fix it involves a lot of command line knowledge, and doing this via forum back and forth will take hours or days.
  3. Owencain thread starter macrumors newbie

    Sep 7, 2012
    Alright so what program should I download? And what steps should I take
  4. murphychris macrumors 6502a

    Mar 19, 2012
    1. Confirm/deny you can't boot anything from this disk: not Mac OS, not Recovery, not Windows.

    2. Boot from something else, like a Snow Leopard or Lion or Mountain Lion DVD.

    3. Find the Terminal application and launch it.

    4. Type these commands and then take a photo of the screen and post it.

    gpt -r -vv show disk0
    fdisk /dev/disk0

    5. Next time consider a VM for running Windows. It's a lot safer. In the meantime prepare for a lot more steps, it'll probably take all weekend as I'm about to leave for pretty much the whole day, back tomorrow.

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