Boot camp doesn't work on new MBA

Discussion in 'Windows, Linux & Others on the Mac' started by DerAmi, Mar 9, 2015.

  1. DerAmi macrumors newbie

    Mar 9, 2015
    Helllo all,

    I've looked through the forums as well as all over the internet, but I simply cannot find out why my boot camp isn't working. I think it may be a stupid mistake I'm making, but maybe somebody could help? So I reformat my USB drive (4GB of course) and I have 3 different ISOs: Windows 10, Windows 8 and Windows 7. All three are three whole, working (tested in virtual box) versions of Windows. As for my laptop it is a week-old brand new MacBook Air (early 2014) version. The error I'm getting is:

    "Your bootable USB drive could not be created.

    Boot camp only supports the installation of Windows 7 (or newer). Please use an ISO file for the installation of Windows 7 (or newer)."

    What I've gathered from this is that the ISO file may be corrupt, but is this possible that all 3 are corrupt, but somehow still work in Virtual Box?

    Thanks everybody!
  2. Gjwilly macrumors 68030

    May 1, 2011
    SF Bay Area
    Check your flash drive.
    It must be USB 2.0, it must be formatted as FAT-32, and it must be partitioned as MBR.

    And your ISOs must be x64.
  3. yjchua95 macrumors 604

    Apr 23, 2011
    GVA, KUL, MEL (current), ZQN
    USB 2.0 is only valid for Windows 7.

    I have a USB 3.0 stick as a Windows 8.1 installer and it works fine.

    For the record, I install Windows in UEFI on Haswell and later Macs.
  4. DerAmi thread starter macrumors newbie

    Mar 9, 2015
    Thanks for your replies, guys. Unfortunately, I've made sure of all of that. Yjchua95 could you send me a link with step-by-step installation in UEFI? I will give that a try as I am getting very fed up with Boot Camp not working.
  5. yjchua95 macrumors 604

    Apr 23, 2011
    GVA, KUL, MEL (current), ZQN
    This was how I got Windows 8.1 in UEFI working on my Haswell Macs:

    1. Use an official Windows 8.1 ISO (from MSDN or DreamSpark, for instance)

    2. Have a USB stick ready (doesn't matter if it's USB 2 or 3)

    3. Run Boot Camp assistant.

    4. When rebooting, hold down Option and go into EFI Boot.

    5. Select the partition you want to install to.


    For installation into external drives:
    Connect external drive to Windows VM. You must have a Windows VM in VMware/Parallels/VBox, or a Windows PC. Any existing Windows environment will do.

    What you need:
    install.wim file (obtain this from your Windows ISO)

    Open elevated cmd.exe (run as admin)

    Note: All commands aren't case sensitive, including pathway to files.

    Type diskpart
    Type list disk
    Take note of the disk you want to select
    Type select disk 1 (if your disk is Disk 1)
    Type clean
    Type convert gpt (stop at this point if you're using a Thunderbolt drive)
    Type create partition EFI size=100 (skip if installing in BIOS-CSM)
    Type format quick fs=fat32 label=EFI (skip if installing in BIOS-CSM)
    Type assign letter=S (skip if installing in BIOS-CSM)
    Type create partition primary
    Type format fs=ntfs quick label=W2G (or any other name you wish for label)
    Type assign letter=E
    Type exit

    Open up File Explorer. In your C drive, create a new folder named WIN2GO.
    Put the install.wim file in this folder

    Back in cmd.exe:
    Type dism /apply-image /imagefile:C:\WIN2GO\install.wim /index:1 /applydir:E:\ (this process will take quite a while)
    Type E:\Windows\System32\bcdboot E:\Windows /s S: /f UEFI (use this one for UEFI installation)
    Type E:\Windows\System32\bcdboot E:\Windows /s E: /f ALL (use this one for BIOS-CSM installation)

    Restart your entire Mac. After the chime, hold down Option and when prompted to select your boot drive, select EFI Boot.

    Proceed installation normally.

    After installation, install Boot Camp drivers. Feel free to trash the VM once you're done too.

    For best results, use USB 3/Thunderbolt. If you don't have USB 3, use Thunderbolt. If you have neither, stick back to the internal drive :)

    Note: This method involves reformatting the entire external drive.

    For Thunderbolt drives, just boot from the Windows USB installer and install directly onto the TB drive. Windows sees TB drives as an internal PCIe connection. However, you must format the TB drive as GPT first.

    CAUTION: Windows can only be installed in UEFI flawlessly on Haswell Macs and later. Ivy Bridge and earlier Macs can only run Windows in BIOS-CSM flawlessly. Attempts to boot a UEFI installation of Windows on an Ivy Bridge or earlier Mac will result in driver issues.

    UEFI-compatible Macs:
    MacBook Air (mid-2013 and later)
    iMac (late-2013 and later)
    Retina MacBook Pro (late-2013 and later)
    Mac Pro (trashcan shape)
    Mac Mini (late-2014 and later)

    Non-retina MBPs are not UEFI compatible.

    WinToUSB basically does the same thing, but doesn’t always work because WinToUSB doesn’t really take into account between BIOS-CSM and UEFI Macs; it only uses one method for all (which may result in boot failures and other problems).
  6. DerAmi thread starter macrumors newbie

    Mar 9, 2015
    Thanks for your reply. However, you do realize that the entire reason I created this thread was because I can't use Boot Camp, right? I don't get past this error message.
  7. yjchua95 macrumors 604

    Apr 23, 2011
    GVA, KUL, MEL (current), ZQN
    Your ISO files are probably the culprits.
  8. DerAmi thread starter macrumors newbie

    Mar 9, 2015
    Even though they all work perfectly fine in Virtual Box?
  9. yjchua95 macrumors 604

    Apr 23, 2011
    GVA, KUL, MEL (current), ZQN

    Virtual Box installs Windows in BIOS-CSM.

    Your Haswell MacBook Air installs Windows in UEFI.

    Perhaps your Windows ISOs somehow lack the UEFI stuff, but I could be wrong.

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8 March 9, 2015