1. Download the tools
While Microsoft Windows doesn't have that much in common with the version of Linux that runs on the Raspberry Pi, it doesn't mean Windows users are at a disadvantage.
This is because the types of applications that run on Windows are just as diverse, and it's an operating system that can lend itself to so many different uses, that the do-everything attitude behind Windows is just as applicableto Linux.
You can even find a Linux-like command line if you look close enough, and many pieces of open source software have been built to run on Windows. So the two worlds aren't that far apart.
Windows users also benefit from having the easiest and least-risk installation routine, thanks to a piece of open source software called Win32 Disk Imager, so your first step should be to download a copy.
It doesn't need to be installed, because the download is a ZIP file which, when uncompressed with a right-click > Extract All, contains everything needed to run the application directly. It should also go without saying that you'll need a copy of the Raspbian image file for writing to your SD card. But this method will work for any Raspberry Pi operating system you might want to install, as well as writing other images to an external USB device.
Check your USB storage
But before we run the image writing tool, we need to make sure the SD card has an identifiable volume name and contains no data you want to keep.
Many Windows PCs include an SD card reader built in to the case, so you might want to try using this first. However, there have been quite a number of problems reported when users attempt to use these to create a bootable version of Raspbian. This is something to be aware of if you run into problems.
We've always had great results from using an inexpensive external USB SD card reader, which is what we're using here. With this inserted, you should find the device appears in your Computer overview from the Windows file manager. It's usually labelled as Removable Disk, and to the right of this you'll see a drive letter. In our example, it's (E. You need to remember this.
You should also open up the drive from Explorer and make sure there's nothing on there you want to keep, because we'll be overwriting everything with the Raspberry Pi operating system. Which is exactly what we're going to be doing in the next step.
2. Launch Win32 Disk Imager and write the data
It's now time to launch the executable we unzipped from the download. Windows will probably warn you that there's a risk to running something downloaded from the internet. If you want to be certain your files aren't infected with some kind of virus, you ought to scan it with your virus checker.
Make the most of this, because after you've got used to Linux, you won't have to worry about your files getting infected again.
When the main application window opens, you'll notice a very sparse interface that isn't that clear. There are two buttons, one for locating the image file and another – just to the right of this – is for selecting the device where you're going to write code from the image file.
Click on the small folder icon and use the file requester that appears to locate your Raspbian image – the requester is already configured to show only files with an IMG file type, so if you can't find it, this will be the problem.
Secondly, use the tiny 'Device' button to select the destination. As all data on the destination is going to be overwritten, it's important to get this right, and it's the reason why we checked for the drive letter in the previous step. You need to make sure it's the same. Win32 Disk Imager normally guesses this correctly, but it's worth checking.
Write the data
When you've double-checked everything is configured correctly, click on the 'Write' button. A warning will pop up to say that writing to a physical device can corrupt the device, but you can safely ignore this.
Your external storage is going to be written to at its lowest level, changing the partition table and some of the formatting, which is why this warning appears. But this low-level is also necessary to get the RPi booting.
After saying 'Yes', the first thing you should check for is any access LED on your USB device. If this starts flickering, you've got the correct device and you can go and make yourself a drink while the data is written.
If not, you need to make triple sure you've got the correct device because this kind of low-level copy on an external hard drive could make it unusable. If you need to stop to check, hit the 'Cancel' button before the process gets any further.
Writing the image can take around 20 minutes, depending on your hardware, and you'll see the progress indicator in Win32 Disk Imager update as well as a small text field showing you how many megabytes of data are being written per second.
3. Checking the installation and backing up
Before putting your freshly made SD card into your Raspberry Pi, it's worth having a quick check to make sure the write process worked as expected. It's also a good way of learning a little about how the SD card has been formatted.
You could look again at your computer's device overview to check that the files stored on your SD card aren't the same as before. But you won't be able to get any further information, because one of the partitions on your SD card is now formatted with a Linux filesystem – making it unreadable in Windows.
The solution is to use one of Windows' built-in administrator tools, and it can be found by searching for Create And Format Disk Partitions within the desktop.
Selecting the top result will open the Disk Management application, and within its main window you can see details of all the storage connected to your machine. Locate your SD card volume – ours was E – and look at its partitions in the table below.
You should see three – one for booting, which is a 56MB FAT partition, one holding the Linux filesystem, and the remainder of the space marked as unallocated. If you see these three, everything has gone well.
Back up your Raspberry Pi
Another excellent feature of the Win32 Disk Imager tool is that it can do the reverse of what we just did. It can take an SD card (or any USB storage device) and turn it into an image file.
This is a great way of taking a snapshot of your Pi's operating system. If, for instance, you spend some time modifying your setup, adding packages and adjusting configuration files, you can come back to your Windows desktop and use the 'Read' option in the main window to copy the contents of the storage device to a single file.
You can then use this single file as a new start point if you need to format another SD card, or if you want to give someone else a hand with your own configuration.
It's also great for backup, because the Raspberry Pi can be fickle when it comes to power provision, and random resets can occur, possibly corrupting data on the card. If you've got a backup, you're safe.