It has been nearly two days since the highly anticipated Windows 8.1 Preview has been available for download. For those of you who snagged the .ISO files and are looking to install Windows 8.1 Preview alongside your current Windows 8 installation, this guide is for you.
First, head over here and snag the Windows 8.1 Preview ISO file. If you snag the update from the Windows Store, you will not be able to dual boot the Preview with Windows 8. You must grab the ISO file instead. Once you have downloaded the ISO file, proceed to the next paragraph.
Within Windows 8, head over to the Start Screen and begin typing “Disk Management” until the Disk Management app appears. Select it and you will be taken to Disk Management. Once the window appears, right-click your system drive and select Shrink Volume. Make sure you have backed up any files on your device just in case something goes wrong. You can also create a partition elsewhere but this option is good if you only have one drive. Shrink the drive, giving as much as 20GB for the Windows 8.1 Preview. After you shink the drive, you will see unallocated space. Simply click on the unallocated block and click “New Simple Volume.” Your new drive is ready to go.
You will now need to burn the ISO file into a DVD or create a bootable USB drive. Head over here to download a bootable USB drive tool. Once your bootable USB or DVD media is ready to go, start your computer and let your Windows 8.1 Preview installation begin! Make sure you have the DVD or USB drive selected as the primary boot device in the BIOS. Once the installation launches, choose Custom installation and select the new partition as the installation location and you should be all set with having Windows 8.1 and Windows 8 dual booting alongside each other.
Use this product key when installing Windows 8.1 Preview: NTTX3-RV7VB-T7X7F-WQYYY-9Y92FFurther reading: Windows 8, Windows 8.1