On September 17, 2013, contrary to former public statements, Microsoft released the RTM (released to manufacture) version of Windows 8.1 Pro and Windows Server 2012 R2 to TechNet and MSDN subscribers. This is before the October General Availability (GA) release date.
According to Mary Jo Foley of ZDNet, “Volume License (VL) customers with active Software Assurance (SA) receive a TechNet subscription as a benefit of SA and can download Windows 8.1 Enterprise RTM bits when they are made available”. Also last week Steve Guggenheimer, Corporate VP of Developer Platform & Evangelism for Microsoft, said GA of Windows 8.1 and Windows Server 2012 R2 will be on October 12, 2013.
Like previous versions, Windows 8.1 can be installed as either a clean copy, or as an upgrade to a previous version of Windows. Microsoft has previously announced that there would be no upgrade path from Windows 8.1 Preview to the RTM version when it becomes available. Now that this final copy of Windows 8.1 is released, we have more information. Fortunately, there is an upgrade path, though it is not perfect.
With Windows 7 and previous versions, we only had the ability to upgrade from the previous version of Windows. In the case of Windows 7, we could upgrade from Vista but not from Windows XP or earlier version. If you did want to upgrade, then a clean install was required.
When Windows 8 was released we had new options. Upgrading from the immediate previous version (Windows 7) would allow for a full upgrade carrying over applications, user settings, and data. Upgrading from older versions, such as Windows Vista were still possible, but only data would be copied over (My Documents, etc). The previous Windows installation (including Windows and Program Files folders) would be moved to a folder in the root of the C-Drive named “Windows.old”, so you wouldn’t lose anything, it just would be carried over as part of the upgrade.
As I mentioned earlier, Microsoft had said that all of us beta testers would not be able to upgrade from Windows 8.1 Preview to the full version of 8.1 RTM. Thankfully they threw us a bone and made an exception.
Upgrading from Windows 8.1 Preview to Windows 8.1 (RTM)
If you are running the Windows 8.1 Preview edition, simply pop in the DVD or USB drive with the Windows 8.1 RTM installation files (or burned ISO). When the installation screen comes up, select upgrade. You are now presented with the option to upgrade carrying over only your personal data files.