Getting Windows 7 onto a USB stick using Ubuntu

I spent way too much time trying to do this so maybe this will save someone else some time.

I haven’t owned a copy of Windows for years, and have been using Ubuntu as my solitary home and office OS for some time. Last week though, I decided I should have a copy of Windows 7 since there’s some software I can’t run without it (my hardware is pretty new, and it seems to take Linux about 6-12 months to catch up with changes in hardware, especially graphics).

So, after a bit of hunting, I discovered it was possible to purchase Windows 7 in downloadable ISO format at http://emea.microsoftstore.com

Great, I thought, that’s pretty progressive of Microsoft! Unfortunately their helpfulness ends there, as the only instructions for actually using the ISO revolve around DVD burners and/or assume you already have Windows (of some sort) installed. I didn’t buy a DVD drive with my last computer build because I haven’t actually needed to use one for a long time.

So, if, like me, you have Ubuntu as your only OS and no DVD drive, it seems like you’re kinda up the creek. Fortunately, this is actually pretty easily remedied. This guide does assume some familiarity with both Ubuntu and partitioning and I’m not big on tech support, so consider yourself forewarned

You need:

1. A USB key that you can afford to wipe completely (at least 4GB)
2. Your Windows 7 ISO of choice (32 bit and 64 bit varieties are available from the store) and the serial (it’ll be emailed to you).
3. A connection to the Internet on your Ubuntu machine (or just read the guide and preinstall anything you see mentioned)
4. A willingness to nuke whatever OS you already have installed, because Windows takes no prisoners (blindly overwrites the Master Boot Record).

Now, technically 4 can be alleviated by recovering grub, but it’s a bit of a roundabout process, and my Ubuntu machines are all basically thin clients. Important documents are stored in Dropbox, my code is on Github, my music, etc is on external drives and almost everything else is also stored remotely or run in the browser. If you don’t want to lose your Ubuntu install, I imagine the guide on the Ubuntu Community Wiki is where you’ll want to look after this.

Important: when you’re downloading the ISO, do not bother with “Part 1″ – it is a boot sector editor for Windows and will be useless to you. Download only “Part 2″ as it’s the ISO (you can only do this about three times, so try to download and store the ISO the first time round).

Partitioning the USB key

We’re going to prepare this USB key with gparted. Disk Utility won’t do (since it won’t allow you to set a device as bootable). You might have this installed already, but if you’re running a fairly fresh copy of Ubuntu, you’ll need to install this using Synaptic. Once it’s installed, you should find it under System->Adminstration->GParted Partition Editor.
Insert your USB key, start up Gparted and select the key from the drop down in the top right. It’ll be something like /dev/sdc, with the size of the drive in brackets next to it.
Delete any partitions that are on the drive, and create a new NTFS one, applying the changes.
Right click on the device, and select “manage flags”. Set the “boot” flag and nothing else.

Extracting the ISO

You may need to eject and re-insert the drive for it to appear, at this point you need to open up your freshly downloaded ISO using the Archive Manager. Do not “mount” the ISO as it will not be usable.
Extract the contents of the archive straight onto your newly formatted (and bootable) USB key. Once this is completed, eject the drive and voila, you have a bootable USB key with Windows 7 on it!