Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have been really scratching my header over how to install Windows 8 dev preview from a USB hard drive. It is an iso file. There is a Microsoft program that will easily set up a USB flash drive to install from, but it won't work with a USB hard drive.

I've searched Google but cannot find an answer to this seemingly simple question. How do you install Windows from a USB hard drive? I've read that I can use disk management to 'mark partition as active' and then extract the contents of a mounted iso into that volume... but disk management won't let me mark the partition on my USB hard drive as active.

Any ideas?

share|improve this question
Again, apologies if this question seems too simple to bother posting, but i really haven't been able to find an easy solution. So much so that i have almost just resigned myself to buying a 8gb usb flash stick to complete the task. – Daniel Gratz Oct 20 '11 at 8:39
up vote 1 down vote accepted

Ok so you don't need to do everything from GUI. Here is a tutorial which works as a charm.

share|improve this answer
ahh diskpart... but does the partition HAVE to be fat32? Can it be ntfs and still work? – Daniel Gratz Oct 20 '11 at 8:55
I think you should follow the tutorial. Maybe it will work maybe not. Just copy your data and make the partition fat32. Or you could try to convert it with some partition manager. – v01d Oct 20 '11 at 9:01

How to: Windows To Go

Windows To Go is a new feature of Windows 8 that allows enterprises to provision a full corporate environment that will boot from a USB drive. Once the instance of Windows 8 is booted it functions and is controlled by standard enterprise management tools such as SCCM and Active Directory group policies.

Work at home and disaster recovery are the primary use cases as Windows To Go can transform any PC into a corporate PC with your application stack, all on a USB drive. Windows To Go is also perfect for trying out Windows 8 on your primary machine without destroying your current OS.

To begin you will need the following:

  • 32 GB or larger USB Drive (It can be a USB Hard Drive)

  • A Windows 8 PC to build the USB drive on.

  • Windows 8 DVD ISO.

  • A copy of Imagex.exe from the Windows 7 Automated Installation Kit installed on Windows 7 or XP. ImageX can be found in C:\Program Files\Windows AIK\Tools\amd64 or C:\Program Files\Windows AIK\Tools\x86.

Creating the Windows 8 To Go USB Device

  1. Windows To Go requires a specific partition setup in order to function. We will use diskpart to create the new partition setup. Launch an administrative level command prompt from the Start Screen.

  2. Make sure that your USB Drive is plugged in and then type in diskpart and hit Enter.

  3. Then list the available disks by running list disk and you should see your usb device.

  4. Select your USB drive by typing select disk # and hit Enter.

  5. Clean the partitions on the disk by typing clean and hit Enter.

  6. Now create the partition by running the following command:

    create partition primary

  7. Select and format the new boot partition by running the following command:

    format fs=ntfs quick

  8. Set the partition active by typing active and hit Enter.

  9. Exit Diskpart by typing exit.

    enter image description here

  10. Now double click the Windows 8 ISO you downloaded to mount it in Windows 8. Browse to the ISO files in Windows Explorer and copy \sources\install.wim to the same folder as you copied Imagex.exe.

  11. Identify the drive letter assigned to your USB drive by Windows Explorer and run the following command from the folder that contains Imagex.exe and install.wim:

     imagex.exe /apply install.wim 1 d:\

    Replace d with the drive letter of your USB drive.

  12. Once the image has applied you need to setup the boot record on the USB Drive. At the administrative level command prompt run:

     bcdboot.exe d:\windows /s d: /f ALL

    Replace d with the drive letter of your USB drive.

After the command has completed running you are ready to use your new Windows To Go USB device.

Credits go to Steve Sinchak @ for the original article.

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .