Month: May 2009

Install Windows 7 from USB Flash Drive

Update: Microsoft has released a very useful open source tool to create USB flash drive for installation. Have a look at Windows 7 USB/DVD Download Tool at CodePlex. – 01/01/2010.

I recently bought an Acer One Netbook which comes with Windows XP preloaded. Since these Netbooks come without built in DVD drives, upgrading to another OS is a challenge. With the high storage capacity USB drives becoming cheaper by the day it is a perfect medium to installing Windows.  Although this tutorial is for Windows 7, you can use these steps to install Windows Vista as well.


  • A Computer or Netbook that can boot from USB Drive. Check your BIOS for boot options, It should have an option to boot from USB disk or Removable drive.
  • A computer with an OS and/or software that can mount an ISO file.
    On Windows, I prefer using Slysoft Virtual Clone Drive to mount ISO. It supports both x86 and x64 bit platforms and is free.
  • USB Flash Drive with 3 GB or more space.
  • Windows 7 ISO (or Windows Vista ISO)
    Microsoft has published Windows 7 RC for everyone to download and test. This version can be used for 1 year. You can download Windows 7 from Microsoft Technet Website.

Prepare your USB Flash Drive

In order to boot from USB Flash Drive – you will need to mark the USB flash drive partition as Primary and format it in FAT 32 mode. Please be careful as while performing these steps. An incorrect step can render your current installation useless.

Step 1 – Open Command Prompt

Open command prompt in Administrator mode. (Click on) Start Button –> (Click on) All Programs –> (Click on) Accessories –> (Right Click on) Command Prompt –> (Click on) Select Run as Administrator –> (Click) Continue. You should a command prompt start “Administrator: “ in the title like below.

New Command Prompt

Step 2 – Setup USB Drive as Bootable

These following steps are very straight forward, but be careful with these steps, make sure you select the right drive. Read these steps and look at the screenshot before you start entering these commands.

  1. Enter command diskpart
  2. Enter command list disk – this will list drives on your computer. Check the size column and note the Disk ### for your USB drive
  3. Enter command select disk #, here replace # with the number of your USB drive.
  4. Enter command clean
  5. Enter command create partition primary
  6. Enter command select partition 1
  7. Enter command format fs=fat32 quick
  8. Enter command exit

command window

Copy Windows 7 Installation files

Mount the ISO that you have downloaded from Microsoft Website and copy all the files to the root of your USB Flash Drive

file explorer

Reboot your computer & set the option in BIOS to boot from USB or Removable Drive

Nice and Easy. Now wait and see how fast Windows 7 installs.