Windows 7 Upgrade media can be used to perform a clean install of the operating system. Using an undocumented workaround you can fool any Upgrade version of Windows 7 into installing itself on a PC without upgrading a previous OS install.
Install Windows 7
Boot your PC with the Windows 7 Upgrade DVD. After the preliminary loading screen, click the Install Now button to trigger 7 Setup. In the next screen, you normally enter your product key. However, there’s a little-known trick in Windows 7 Setup whereby you can simply skip this phase and use the install media (Upgrade or Full, any version) to perform a clean install of virtually any 7 product edition. What you do is leave the Product Key field blank, deselect the option titled “Automatically activate Windows when I’m online,” and then click Next. 7 Setup will ask you whether you would like to enter your Product Key before continuing. Click No.
In the next Setup screen, you’ll be presented with a list of the Windows 7 product editions you can install. Choose the product edition you actually own. You’ll be asked to verify that you’ve chosen the correct version. Do so to continue past the End User License Agreement (EULA) screen.
In the next screen, you select the type of install. Choose Custom (Advanced) instead of Upgrade. Next, you choose the partition to which to install Windows 7. If you need to format the disk, select the Drive options (advanced) option to do so and then continue.
Now, Setup copies the 7 install image to your PC, expands it, and installs Windows. This phase of Setup should take about 15 to 20 minutes and trigger at least one reboot. When 7 is installed, you’ll step through the penultimate phase of Setup in which you enter, in succession, your user name and password, computer name, and the date, time, and time zone. Then Setup runs its final task, a performance test that could take about 5 minutes. If everything goes well, and you’re running fairly modern hardware, you should hit the Welcome screen and, after logging on, the new 7 desktop less than 30 minutes after you began this process.
What you’ve installed is decidedly temporary. You’ve got 30 days during which you can run this non-activated version of Windows 7. If you try to activate Windows now, it will fail, because you’ve performed a clean install of 7 and you only have an Upgrade product key.
What to do, what to do? If you read Microsoft’s support note carefully, you will have seen that the Upgrade versions of 7 support upgrading from “a compliant version of Windows, such as Windows 7, Windows Vista, Microsoft Windows XP.” Well, you just installed Windows 7, so why not just upgrade from this install? That’s right: You’re going to upgrade the non-activated clean install you just performed, which will provide you with a version of the OS that you can, in fact, activate.
To do this, just open Computer and double click on the icon for the DVD drive that contains the 7 Upgrade media. Run Setup again, this time from within 7. Choose Install Now, and then “Do not get the latest updates for installation” in the next screen. Then, in the now-familiar Product Key phase, enter your product key. It’s on the back of the pull-out 7 packaging. You can choose to automatically activate Windows when online or not, it’s your choice. In the next screen, accept the Windows EULA.
Now, choose the Upgrade option. Windows will install as before, though you might notice that it takes quite a bit longer this time. (Upgrade installs seem to take up to 45 minutes, compared to 30 minutes or less with clean installs, and reboots at least one additional time.)
Because you’ve just completed an upgrade install, you won’t be prompted to enter your user name and so forth (only the time zone screen is presented). Instead, you’ll just boot directly to the Welcome screen when the performance check is complete. Using the user name and password you created during the first install, logon to Windows.
Once again, you have 30 days in which to activate 7. However, this time activation will work: To activate 7 immediately (unless you told it to do so during Setup), open the Start Menu, right-click Computer, and choose Properties. Then, at the bottom of the System window that appears, click the link titled Activate Windows now.