If you are already having Windows 8 installed on your PC, then you dont need to worry about downloading Windows 8.1. According to Microsoft all Windows 8 users with an original copy of the OS will be provided with a free upgrade to windows 8.1. UPDATE ( 17/8 ) : Windows 8.1 is now officially available for update from the Windows 8 app store. If you already have an activated copy of Windows 8, then you can visit this link to upgrade to windows 8.1. Closed Solved 28 answers Last reply Oct 9, 2014 Best Answer. Jan 10, 2013 More about change windows Ask a new question. Configuration Windows 7 How To Windows 8. You can use it for installing to any compatible system with any other legit key. # The same product key can be used for downloading ether 32/64-bit Windows 8 i.e. the key is common for both versions. Step 1 : Download Windows8-Setup. exe from here. it is 5.2MB in size. Step 2 : Decide which Windows Pro version you want either 32-bit or 64-bit. Well do note that you can install 64-bit only if your processor supports it. Just enter your keys and viola, your download will commence. Step 5 : After the download is completed, before installing the upgrade, we suggest you to create an iso or a USB drive backup for future setups. Alternatively if you want to upgrade to windows 8.1 from windows xp or windows 7, then you will have to buy a retail copy of windows 8.1, which will cost you around 120 for the base version and 200 for windows 8.1 pro edition. Windows 8 seems to be getting good reviews from users except from few. Well many of us are still thinking whether to upgrade or not. For all those who are not aware of the Windows Upgrade program, Microsoft is offering you a Windows 8 Pro. The major focus of this release is networking and security with an advanced Windows Defender with all the goodness of Microsoft Security essentials. Moreover, it has features for safer browsing as the introduction of Internet Explorer 11.