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How to install Windows 8 Preview using Boot Camp

Since the release of the first developer preview of Windows 8(s msft), Mac (s aapl) users have been downloading it to run in virtualization software such as Parallels and VMware Fusion(s vmw). It’s also possible to install the preview on Boot Camp, the tool built in to Mac OS X which allows you to dual-boot your Mac into other operating systems.

What you’ll need

  • A Mac with at least 2 GB of RAM and at least 20 GB of free hard drive space.
  • A disc burned using the ISO of the Windows 8 preview, available to download here, with a burning program such as Toast.
  • A hard drive backup, in case everything goes pear-shaped.


  1. First, open the Boot Camp Assistant, which can be found at Applications > Utilities > Boot Camp. Once opened, you’ll see a screen explaining what Boot Camp does, and warning you to make a backup.
  2. After clicking Continue, you’ll be asked whether you want to download Windows support software or if you have it on a CD or DVD. Make sure to select the second option; you won’t actually be installing the support software, since it won’t work with the Windows 8 preview. Then click Continue again.
  3. The next step is to choose how large to make the Window partition on your hard drive. A Boot Camp operating system must be installed on a partition of your internal drive; it can’t be used on an external drive. The partition you create should be at least 25 GB in size, so there’s enough room for the OS and anything extra that might end up there, like files or applications. Next, click Partition.
  4. Once your drive is partitioned, it’s time to install Windows. Again, the Windows 8 preview needs to be burned to a disc in order to install. Boot Camp should detect the disc once it’s inserted and allow you to continue installing. Click Start Installation. Your computer will now restart and boot from the Windows disc.
  5. Follow the instructions on screen. When the installer asks you where to install Windows, select “Disk 0 Partition 3 BOOTCAMP” and then click Drive options (advanced). Choose Format from the options that appear to format the partition to NTFS, the file system Windows requires.
  6. Follow the onscreen instructions again. Once Windows has installed, your Mac will automatically restart into Windows.

Since the Boot Camp support software for Windows won’t work with the developer preview, you won’t be able to install the Boot Camp tools on Windows. That means that to boot back into your OS X partition, you’ll need to restart your Mac with the Option key on the keyboard held down. You’ll be shown a list of available startup drives, from which you can choose your main partition where OS X is housed.

Remember this is a developer preview version of Windows 8. That is, it’s essentially alpha software, so things could go very wrong when you use it. Just as Apple suggests when using developer previews of OS X, you might not want to install Windows 8 on your main computer, and make sure to back up before you do any installations.

16 Responses to “How to install Windows 8 Preview using Boot Camp”

  1. Kevin Reña

    i have MBP 13″ with mac os x Lion, when i try to install windows 8 at bootcamp, it restart and turn the screen into black and it say: “windows failed to start. a recent hardware or software change might be the cause.”
    i need help guys. thanks!

  2. Hi Justin I am trying to install bootcamp for dev build after changing compatibility but using setup.exe gives me message “bootcamp x64 unsupported on this comp.” , running bootcamp64.msi through cmd or otherwise tellse me to run it from setup.exe. How did you install it for your machine?

  3. You must install the boot camp software or it will run like a bag of bolts! My trackpad was horrendous to use until I installed the boot camp software. I have Win 8 running on a last edition MacBook sweet as a peach now! I even kind of like it!!