How to Boot Windows 7 Using a USB Flash Drive
Written on August 25, 2009 by Kay
Optical drives are starting to show their age. Sure, a DVD disc can hold a lot of data, but reading all that binary goodness with a laser eye is becoming a slow process when compared to the read/write speed of flash memory devices. Still, DVDs are light years ahead of installing Windows from floppy disks! One of the reasons why Windows takes a while to install is because all the operating system files need to be pulled from a disc and output to your hard drive—a time consuming process. You can greatly speed up installation by bypassing the DVD disc altogether, installing Windows from a USB flash drive. Wouldn’t you like to shave off a half hour from a Windows installation, especially if you are installing it on more than one computer?
Read on and I’ll show you how with Windows 7 and a USB flash drive.
4GB Flash Drive
First off, the Windows 7 ISO—an ISO is a disc image—weighs in at approximately 2.5 gigabytes, so you’ll need a flash drive with at least 4 gigabytes of memory in order to store the Windows 7 ISO on it.
Once you have your Windows 7 ISO (beta Windows 7 ISOs were distributed by Microsoft earlier this year) saved to your hard drive, plug in your USB flash drive and remember the drive letter that Windows assigns to it.
Okay, here’s where things get kind of technical. Open up a command prompt and type in diskpart (start menu, run, type in “cmd” without quotes, and hit enter) and type list disk at the prompt. This will list all your various USB devices that you have connected to your PC. Remember your device number from the command prompt output. In this article, we’ll use disk 12 as our hypothetical flash drive.
In the command prompt, choose your dive by typing: select disk 12. Now execute the following commands at the prompt, one by one, after each comma: clean, create partition primary, select partition 1, active, format fs=fat32, assign, exit.
The above commands may look weird and cryptic but all they really do is tell Windows to make a primary partition on your USB flash drive, activate said partition, and format it FAT32 style, an old file system format from the days of Windows 95.
Okay, here comes more obscure commands but it’s almost over. Now that we have our USB flash drive properly prepared and formatted it’s time to shuttle the Windows 7 files from the ISO to your flash device. Simply insert your Windows 7 DVD into your optical drive or mount your Windows 7 ISO with a utility such as Daemon Tools, a very useful program that makes Windows think that it’s a virtual drive. Back inside a fresh command prompt, type in: xcopy d:*.* /s/e/f j:
In the command above “d” is my mounted Windows 7 disc and “j” denotes my USB flash drive. Now, hit enter and sit back and watch as all the files that comprise Windows 7 are whisked away to your flash drive. After the process has concluded, you will then have a bootable Windows 7 USB flash drive.
Lastly, you must make sure you tell your computer to boot from your USB device when it starts up. You can do this by going into your BIOS and changing the order of the boot list. Consult your motherboard’s manual if you need help with this. Not only is installing Windows 7 from a USB flash drive much faster than from a DVD, but you can also hang Windows 7 from your key chain!
THANK YOU VERY MUCH i been trying and trying to find out how to make a boot-able usb and tried sooooo many ways that didnt work and this did now i have a flash drive that i can use to format my netbook but i didnt use win7 i used a vista ultimate iso and it worked great thank you thank you im so glad it worked
Didn’t work… this is the most frustrating thing I have ever done on a computer. Why is this so hard to do??
A few months back I put in a build version 7022 of windows 7. I am now currently in that build of windows 7 trying to put in a legitimate version of windows 7(build 7600) but absolutely nothing is working. I did all of these steps up until the xcopy part, which, when typed in, just gave me a whole list of commands that you can use in the diskpart portion of commandprompt.
I have had it with this and just want something that works. I keep getting popups that right now I don’t have a genuine version of microsoft windows and, i guess because of that, i can’t get any windows updates and have to deal with these popups every 5 minutes. Any suggestions would be great because i have spent hours on end trying load up windows 7 ultimate build 7600 forever… and failing everytime.