Bootcamp Windows 2012 Server install from USB key

Discussion in 'Windows, Linux & Others on the Mac' started by 3KyNoX, Dec 10, 2012.

  1. 3KyNoX macrumors newbie

    Dec 10, 2012
    Hello everyones,

    I have actually some problems to install Windows Server 2012 in a bootcamp partition and from USB key made with WinToFlash software.

    Here is the steps I used :

    - USB install preparation with WinToFlash
    - reFit installation from package 0.14
    - Mac reboot two times
    - Loaded Windows 2012 Server iso in Daemon Tools
    - Made Bootcamp partition from assistant
    - Reboot of the Mac with the usb key plugged.
    - And then I choose my EFI boot from reFit Menu.
    - Then, installation launch and I got error at the step of choosing partition

    The error tells that I could not use MBR partition in EFI mode, and that I must use GPT drive to do so.

    I saw the nice post of murphychris here :

    Which is greatly explained, but I feel a little lost of what to do now.

    Do I have to delete and recreate this partition using gDisk ?

    Will it have bad effect on that bootcamp partition ?

    Do I will boot on that partition without problems after Windows installing using that way ?

    So please tell me what to do.

    Thanks for help.

  2. murphychris macrumors 6502a

    Mar 19, 2012
    Boot Camp prepared drives are not compatible with EFI booting of Windows. Boot Camp Assistant creates a hybrid MBR. Windows when EFI booted will only install and boot from a GPT disk, it complains when it finds an MBR other than a protective MBR. Window when BIOS booted will only install and boot from an MBR disk, it will ignore the GPT if an MBR is found.

    You can use gdisk to create a new protective MBR from the Expert menu, which will replace the hybrid MBR.
  3. 3KyNoX thread starter macrumors newbie

    Dec 10, 2012
    Thanks murphychris.

    Using gDisk, I have to remove Hybrid MBR (4th partition) and recreate it in Protective MBR.

    Does it make changes on the entire disk while creating table and save changes? Because I have my main Osx partition on that disk.

    Can this gDisk operations will prevent to use the partition for Bootcamp as well ?

    Thanks again.
  4. murphychris macrumors 6502a

    Mar 19, 2012
    Well, you're not saying it correctly but you need to create a new protective MBR. This will replace the hybrid MBR.

    It will write a new GPT and MBR to disk - so that's maybe 37 sectors being written. It will not alter the GPT entries including OS X.

    Define Bootcamp, because I don't know what you mean by it. There's Boot Camp drivers from Apple, there's Boot Camp Assistant, and there's the EFI CSM/BIOS. There is no one such thing as Boot Camp.

    A particular Windows installation can be only either EFI bootable or BIOS bootable. It cannot be both (not easily anyway). If you use EFI boot, you can only use GPT partitioning, so you need to remove the hybrid MBR that Boot Camp Assistant created.
  5. 3KyNoX thread starter macrumors newbie

    Dec 10, 2012
    Okay, things more clear.

    I'll make a try on gDisk, I was using fDisk on Debian systems in the past, it looks like related.

    Thanks again for your help murphychris.
  6. murphychris macrumors 6502a

    Mar 19, 2012
    gdisk stands for GPT fdisk. Regular fdisk only manipulates MBRs. gdisk mainly manipulates GPT, but it can do certain things related to MBR like create a hybrid MBR from GPT information; and make a GPT from an MBR. But directly edit the MBR it does not do.

    But if you're familiar with fdisk, you will be comfortable with the interface of gdisk.

    It is the only tool I use for dealing with hybrid MBR issues, as no other tools in my opinion can really be trusted, for sure not Apple's Disk Utility. There are some GUI tools expressly for dealing with the hybrid partition scheme like iPartition (and I think also WinClone and CampTune) but I haven't used any of them.

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