Setting up Windows 7 on a USB drive - updated

I am writing this guide to put Windows 7 on a USB drive as there are many other guides on the internet but none are complete from start to finish and I had to spend a lot of time putting information from lots of places together to be able to do it. Also these steps are the way to do it in Windows XP, Vista may vary. I hope this makes it easier for everyone!

Being a student I took advantage of the Windows 7 student offer  where it costs £30 with a valid .ac.uk student email address. You can even get Windows 7 Professional if you tick the right box at the right time (which is what I did and it costs no extra). The download gives you 3 files - an application file and then "setup1.box" and "setup2.box".
This guide describes how to get these files from this format as downloaded onto a USB stick and ready to be installed on your computer (EeePC or otherwise). If your version is already an .iso file then you can skip the first bit of the guide.

Obviously you will need a (blank) USB stick to put Windows 7 on and it has to be at least 4GB. To make the install quicker you should buy the fastest USB stick you can find (fastest read/write speeds). I bought this one and would recommend buying yours from 7dayshop as they gave me an excellent service and have some fast USB drives and are cheaper than most other websites.

To do this you need a few programs:

• Oscdimg CD/DVD Premastering Utility 
• HP USB Disk Storage Format Tool
• MBR Wizard
• Daemon Tools Lite (the lite version is free)
• Your copy of Windows 7 

Changing the .box files into an .iso:

•  Run the .exe application to extract the .box files. This makes a new folder called expandedSetup. Put the expandedSetup folder in the C:\ root folder.
• Close the Windows 7 installer once it has extracted fully.
•  Download and install the oscdimg.exe
• Put the downloaded oscdimg.exe file into your system32 folder (e.g. c:\Windows\System32) 
• Click on Start -> Run, then type in cmd and press enter.
• Type in: oscdimg.exe –bC:\expandedSetup\boot\etfsboot.com –u2 –h -m -lWIN_EN_DVD C:\expandedSetup\ C:\Win7.iso  (by the way the bit before WIN_EN... is a small L not a 1 or I or anything).
• Once that has run you will have an .iso of Windows 7. You can then burn this onto a DVD and install that way or continue reading this guide to put it onto a USB stick.

 Making the bootable USB drive:

• Install and run the HP Disk Formatter. Select your USB drive in the drop down list and use the NTFS file system. You can just do a quick format. This step isn't essential if you have a brand new unused USB drive but you can be certain if you do this and it is very quick.
• When you drive is formatted install and run Daemon Tools Lite. Right click on the icon in the system tray and open the "Mount'n'Drive Manager". Click on add file (the CD with a + on it) and choose you Win7.iso file. Mount the .iso to a drive letter - I chose I:.
• Extract the MBRWizard .zip file and copy the .exe into C:\ root folder.
• Open cmd (Start -> Run -> cmd) again.
• Type in: MBRWiz /list
• This shows the configured drives on your system. Look for your I: (or whichever drive you chose in Daemon Tools) and not which disk number it is - mine was 1.
• Next type: MBRwiz /disk=1 /active=1 (if your disk number was not 1 swap this in that command).
• If it asks you if you are sure press Y, then enter.
• Next type in: I:\boot\bootsect /nt60 G: (here I: is your mounted drive and G: is the drive letter of your USB drive, swap these letters as appropriate for your machine).
• Open up My Computer or Windows Explorer and copy the contents of your mounted Windows 7 drive (I:) onto the USB stick.

Now you are done, your USB drive is ready to be used to install Windows 7. You will have to change the boot priority on your computer/EeePC to boot from USB first in the BIOS. I will write about this in detail soon when I actually do it myself.

I hope you understand everything in this post, please feel free to leave me questions in the comments and I will answer them when and if I can.

AJ

P.S. I have heard that there is a Windows tool to do this all for you but I have no idea if it works and how to do it - here it is. You are welcome to try it and let me know if it is any good!

Update: This is the Windows USB installer which they have just re-released. It requires a Windows 7 .iso so if you have the .box files then you will need to follow the first part of my guide. It also requires a 4GB USB drive as mentioned earlier.
I haven't had a chance to use it but it looks incredibly simple to use so I would recommend it!