Although there are number of methods available on different blogs through which you can install Windows 7 on USB drive but here is a simplest one. It don't need any DOS commands manipulation like other methods. You can now create Windows 7 installation flash drive with just 2 clicks. Installing Windows 7 from USB is much more fast and ofcourse it saves you from buying and burning ISO on a new DVD.
Requirements / Prerequisites
- USB Stick [4 GB Minimum]
- Windows 7 ISO Image file
First download UNetbootin for Windows and Linux. There is no need to install, just double click on UNetbootin.exe to launch UNetbootin. Now in Diskimage choose ISO file you have downloaded. Now select Type as USB Drive and choose drive letter of your USB stick. Once done, your settings should be just like the screenshot below.
Hit OK and it will take 10 to 15 minutes for copying and extracting files to USB. After that your USB will become bootable.
Now restart your system. Press DEL to go to your BIOS settings. In boot devices priority settings, choose boot from USB flash drives first. Restart your system after saving changes to your BIOS. Now you will see Windows 7 setup being initialized from your USB. Enjoy fast installation.
Even though UNetbootin is basically made to create USB sticks capable of booting various Linux distros but i am amazed that it also worked for Windows too.