At BUILD 2013 conference in San Francisco, Microsoft today released the Preview version of “.1” update to Windows 8. All PC users running Windows 8 can now upgrade their installations to Windows 8.1 Preview by installing this update and then following on-screen instructions.
To help Vista and Windows 7 users, Microsoft is offering Windows 8.1 Preview as an ISO file as well so that interested Vista and Windows 7 users can easily test drive Windows 8.1 on their machines by installing Windows 8.1 in dual boot with Vista or Windows 7.
The ISO file is also useful for those who want to dual boot Windows 8.1 Preview with Windows 8 to avoid reinstalling apps and programs when the final (RTM) build is released.
To download Windows 8.1 ISO file, you need to head over to the below mentioned download link and then sign-in with your Microsoft account (Outlook.com, Live, MSN or Hotmail) to start downloading the ISO file. Depending on your Internet connection speed and load on Microsoft servers, it might take a few minutes to hours to complete downloading the ISO file.
Once you have the ISO file, follow our how to install Windows 8 from ISO file or how to install Windows 7/Windows 8 from USB flash drive guide to successfully install Windows 8.1 on your PC. Mac users can follow our how to install Windows 8 on Mac guide to create a separate partition for Windows 8.1 and then install Windows 8.1 using Boot Camp Assistant.
And if you have a Microsoft TechNet or MSDN subscription, we suggest you download the ISO file from your account to get better download speed.
The download size of Windows 8.1 Preview (x86) is 2660 MB and x64 is 3580 MB.
Note that you’ll need to use NTTX3-RV7VB-T7X7F-WQYYY-9Y92F as the product key to install and activate your Windows 8.1 Preview copy.
NOTE: At this moment, Windows 8.1 ISO files are available to MSDN and TechNet subscribers only.
Visit TechNet to download Windows 8.1 Preview