Update from Windows 8.1 Preview to Windows 8.1
Thank you for using Windows 8.1 Preview. The final versions of Windows 8.1 and Windows RT 8.1 are now available online and in the Windows Store.
The preview is no longer available for download. You must install the final version of Windows 8.1 or Windows RT 8.1 before January 2014 when the license for the preview will expire. If you've been using the preview, you should update to the final edition as soon as possible to avoid an interruption in using your PC.
Updating to Windows 8.1 or Windows RT 8.1
Important: Microsoft is investigating a situation affecting a limited number of users updating their Windows RT devices to Windows RT 8.1. As a result, we have temporarily removed the Windows RT 8.1 update from the Windows Store. We are working to resolve the situation as quickly as possible and apologize for any inconvenience. We will provide updates as they become available.
Your options for updating to Windows 8.1 depend on how you installed Windows 8.1 Preview or Windows RT 8.1 Preview.
Returning your PC to its previous operating system
In some cases you might want to go back to your previous operating system before updating or upgrading to Windows 8.1. You have different options depending on what version of Windows your PC was running before you installed the preview.
When running Windows 8.1 Preview, if you used the Add Feature function to change editions, you might need to reinstall or reactivate using your same edition product key. To find out more about changing product keys, see KB2750773.