A lot has changed in the past year: Wherewas available as an upgrade from all supported versions of Windows at the time—XP, Vista and 7—Windows 8.1 only offers a truly seamless upgrade from Windows 8. And if you try to upgrade from Windows 7 to Windows 8.1, you will discover that your options are quite limited, and that you'll need to reinstall all your applications and reconfigure all of your settings. Fortunately, there's a simple tip that will help you perform a full upgrade from Windows 7 to Windows 8.1.
And it's this simple: Upgrade to Windows 8 first.
If you are a Windows 7 user and you purchase Windows 8.1 today, electronically (using Upgrade Assistant) or via disc-based retail media, you'll discover a nasty problem: When you attempt to upgrade, you're told that you can only bring your personal files forward, which is a limited form of migration, not an upgrade, or bring nothing forward, which is the same as doing a clean install. In either case, you would need to reinstall (and reconfigure) every single application you're currently using.
But if you refer back to my article Windows 8 Tip: Upgrade from Windows 7, you will discover that this process provides a much wider range of choices, including a real in-place upgrade (in which your settings, personal files and applications are retained), a partial migration (keep personal files only), or a clean install (keep nothing). So if you wish to really upgrade from Windows 7 to Windows 8.1, you should upgrade to Windows 8 first. Then you can upgrade from that to Windows 8.1 for free. (And again retain all of your settings, personal files and applications.)
The question is, with Windows 8.1 now available, is it even possible to purchase Windows 8 anymore? Actually, yes. Your local Best Buy, Microsoft Store (Core and Pro) and other retailers still stock the original version of Windows 8. And you can even purchase it online and use the Windows 8 Upgrade Advisor to perform the upgrade. The price is the same as for Windows 8.1: $119.99 for the Windows 8 "Core" Upgrade and $199.99 for the Windows 8 Pro Upgrade.
Once that upgrade is complete, just launch Windows Store and upgrade to Windows 8.1—again, for free—normally.