Microsoft has made available for download Windows 8 Release Preview. This free operating system is the final, feature complete version of Windows 8, which is set to launch to consumers later this year. Here's how to install Windows 8 Release Preview.

Windows 8 is the biggest development in Microsoft's operating system for PCs and laptops since Windows 95 replaced Windows 3. The Metro interface alone is a radical overhaul of the way you are used to working with Windows, and Windows 8 is built from the ground up to work on touchscreen devices, as well as via keyboard and mouse. The Windows Store allows you to install Windows 8 apps. For more on the changes in Windows 8 and how to use them visit Windows 8 Advisor. (See also: Windows 8: the complete guide.)

So here is a quick guide to installing the Windows 8 Release Preview. If you already have the Consumer Preview installed, it will simply be an in-place upgrade. Bear in mind that the free Windows 8 previews are not final code, and so are likely to have bugs. They are also time limited - early next year they will simply stop working, unless you have paid to upgrade to the full version of Windows 8. So we recommend installing Windows 8 on a separate partition or external hard drive, rather than wiping over your existing Windows 7, Vista or XP install. Indeed, the safest option is to install the Release Preview on a virtualisation tool, such as VirtualBox.

For further detailed advice on installing Windows 8 Release Preview, read our article: How to install Windows 8.

How to install Windows 8

Install Windows 8 Release Preview Setup Utility

The simplest way to get Windows 8 is to run the Windows 8 Release Preview Setup Utility (download it here). This will check your system for any hardware and software issues that might complicate the installation, and then obtain the required product key

Once it knows which flavour of Windows 8 to install, the Preview Setup Utility will download the 1.5GB Windows 8 Release Preview file. You'll be offered three options: Install on the current partition, Install to a different partition, or Install later.

Select either of the first two and the setup program will launch. The latter option simply stops the process, and you have to start from scratch (minus the download time) when next you attempt to make the install.

Manually install Windows 8 Release Preview

Microsoft has made great strides in making Windows installation much easier, so you don't actually have to use the Preview Setup utility. Alternatively you can download the Windows 8 Release Preview file, and simply allow it to run. The program will probe your machine and determine whether your hard- and software are compatible.

Windows 8 downloads:

You'll have to right-click the drive you want to partition, then choose Shrink volume and Windows will determine how much unallocated space is available. Right-click on the free space and choose 'Create new simple volume'. Next, follow the setup wizard's prompts to create a new partition.

Burn to a DVD the ISO image you downloaded. If you're running Windows 7, you simply need to double-click the file to launch the Windows Disc Image Burner tool. If you're running Windows Vista or XP, we recommend downloading the free CDBurnerXP.

Now follow the onscreen instructions. You'll need a product key to install Windows 8 Release Preview: everyone can use TK8TP-9JN6P-7X7WW-RFFTV-B7QPF.

Click Install Now to proceed. Choose Custom install, then select the new partition you created or you will overwrite your existing installation. During the installation process your computer will reboot itself several times. Eventually, the machine will boot into Windows 8.

Buy The Complete Guide To Windows 8.