How to Create Bootable USB for Windows 8 Developer Preview

“..Like many folks, after watching the BUILD keynote this morning, I couldn't wait to get home and install Windows 8 Developer Preview on my laptop. The instructions for installing Windows 8 are simple enough. The only fly in the ointment is that installing Windows 8 requires a DVD to create an install package…”

So Mount the ISO first lest say it is mounted on I: drive

Here are the steps to format a USB flash drive.

1. Insert a USB flash drive into your computer
2. Start a Command Prompt as an Administrator and type diskpart. This starts the Disk Partition tool which you need to use to format the flash drive. Once you see the DISKPART command prompt, type in the following commands
3. DISKPART> list disk /* shows list of active disks */
4. DISKPART> select disk # /* # is the number for your USB flash drive */
5. DISKPART> clean /* deletes any existing partitions on the USB flash drive */
6. DISKPART> create partition primary /* create a primary partition on the USB flash drive */
7. DISKPART> select partition 1 /* select the newly created partition */
8. DISKPART> active /* make the new partition active */
9. DISKPART> format /FS:NTFS /* format the USB drive with NTFS file system */
10. DISKPART> assign /* assign a volume and drive letter to the USB drive */
11. DISKPART> exit /* exit Disk Partition */

At this point, your USB flash drive should be showing up in Windows Explorer and have a drive letter assigned to it, e.g. F:\.

Make the USB flash drive bootable

We just need to make the USB flash drive bootable before copying the files. To do this, you can use the Boot Sector Registration Tool (bootsect.exe) which is located in the boot folder of the Windows 8 ISO image.

1. Start a Command Prompt as an Administrator and CHDIR into the boot folder of the Windows 8 ISO image, e.g. I:\boot where I:\ is the drive where the ISO image is mounted
2. Type bootsect /nt60 E: /* where E: is the drive assigned to the USB flash drive */

Step 3: Copy the Windows 8 files onto the USB flash drive

From a command line, use XCOPY to copy the Windows 8 files to the USB flash drive . In the example below, I:\ is the drive where the ISO image is mounted. F:\ is the USB flash drive.

XCOPY I:\*.* F:\ /E /F /H

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