Boot and Install Windows from a USB thumb drive

Installing Windows from a thumb drive is vastly superior to burning a copy to a DVD which will fill some landfill somewhere with toxic stuff. Not to mention it's about 50x faster to install Windows from a USB Thumb Drive.

How do you get the bits onto the thumb drive so that you can boot from it and do a clean install?

Update: Microsoft has created the Windows 7 USB/DVD Download tool to make this very easy.

I used this guide as a set of directions - http://kurtsh.spaces.live.com/blog/cns!DA410C7F7E038D!1665.entry

1. Get a USB Thumbdrive between 4-32GB.

If the drive is larger than 32GB, Windows cannot format it as FAT32, so an alternate utility must be used. Windows can still read FAT32 partitions larger than 32GB, though some devices cannot.

2. Run cmd.exe as administrator and enter the following commands followed by Enter

1. diskpart
2. list disk
3. select disk # (where # is your USB drive as determined from step 2)
4. clean (This step will delete all data on your flash drive!)
5. create partition primary
6. active
7. format fs=fat32 quick
8. assign
9. list volume
10. exit
11. bootsect.exe /nt60 F: /mbr (where F: is the drive letter of your USB drive as reported by list volume)

3. Copy the Windows files from the ISO or other source using robocopy

robocopy.exe E:\ F:\ /MIR

where E:\ is the source and F:\ is the destination. Drag-and-drop or copy/paste can also be used, if you know what you're doing.

Configure your PC to boot from the USB drive

In some machines the USB thumbdrive will appear to the BIOS as any other hard drive. You need to muck with the boot sequence to place the thumbdrive higher in the boot order than the local hard drive.

Note that after you do this you might want to reset the boot order in order to ensure that BitLocker doesn't detect boot changes based on the fact that the thumdrive is missing if it was there when you encrypted your drive.

I found two problems with the accepted answer:

1. It assumes the usb drive is disk 1 for DISKPART.
   This can be resolved by using the LIST DISK command prior to SELECT DISK # to determine the correct disk number.

2. The usb drive did not appear as a bootable device to the target machine.
   This can be fixed by running the bootsect utility off the Windows installation DVD.
   

   Before copying the contents of the Windows DVD:

   1. Run cmd.exe as Administrator
   2. Select your optical drive (assumed to be D:)
   3. Type CD boot
   4. Type D:\boot\bootsect.exe /nt60 U: (where U: is your USB drive)

Adding these extra steps I was able to install Windows 7 from a USB HDD onto a Samsung NC10 Netbook.

If this proves unsuccessful some other techniques (including the accepted answer with the above steps) can be found at http://www.bootdisk.com/pendrive.htm.

There is a tool (YUMI) to achieve this. I think, it is fastest and painless way of preparing a (multi)bootable usb. You can put many systems (Windows, Linux, HBCD etc.) into one flash drive. And you can also use an external drive.

Try Rufus

Rufus is an utility that helps format and create bootable USB flash drives, such as USB keys/pendrives, memory sticks, etc.

It can be especially useful for cases where:

• you need to create USB installation media from bootable ISOs (Windows, Linux, UEFI, etc.)
• you need to work on a system that doesn't have an OS installed
• you need to flash a BIOS or other firmware from DOS
• you want to run a low-level utility

Despite its small size, Rufus provides everything you need!

Quick tip I hope will help people going through the same pain as me when trying to create a thumb drive for Windows Server 2008

I had an old USB led around, but it wouldn't mount for me to run diskpart on it.

Turns out it was formatted in FAT16. Mount it on a laptop with a proper OS, reformat it to FAT32, then plug it back into the Windows Server 2008 box and it mounts. Then run diskpart as above.