Windows 7 Upgrade Installation Foo

  • peter 

It is, again, the time to re-install my virtual machine with Windows 7. So far so bad. I don’t like to install Windows in the first place but from time to time I needed it and Windows 7 is actually not that bad. But for a good reason ($$$) I bought an upgrade license of the Ultimate Edition. Now this would force me to install Windows Vista first, just to perform an upgrade. Sounds kinda silly, doesn’t it? So I won’t do it and I dug out an old c’t magazine (issue 24/2009) where they discuss a way to install the upgrade without going the normal upgrade path. I am sure there are some other resources out there that explain the same thing, but here is my take on it.

Step 1 – Installation from DVD

Because the setup is the same for all versions it has no clue what version you will install. The whole intelligence, if you want to call it that way, sits in the license key. As a result the setup is denying to install the OS only after entering the upgrade license key, with the false message that the key is invalid. Just skip the key entry part in the setup and continue without a license key. Setup will continue to install Windows but the activation will fail.

Step 2 – Activation

To get Windows to activate one has to pretend that this is not a fresh install but an upgrade from an older Windows version. And you guessed right, you have to dive into the registry. Start regedit by typing it into the search text field in the start menu or in whatever way you like to start it. Once started go the following key:

HKEY_LOCALE_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Setup\OOBE

In that key you change the value of the entry MediaBootInstall to 0 (zero).

The last step is to reset the activation and licensing mechanism of Windows. Type cmd into the search field of the start menu and hit CTRL+SHIFT+Enter to start a text console (formerly known as DOS box) with elevated rights. Of course you will have to confirm a dialog to really get the elevated rights.

In the newly created text console window you enter the following command:

slmgr -rearm

This will reset the licensing and activation manager, but it might take some time for Windows to react. Finally Windows will ask to reboot and you will boot into an OS that thinks it is freshly updated from another Windows version.

Step 3 – Entering License Key

Last but not least you have to finally enter your license key. So far the key might feel like the redheaded step child, but now it can shine. In order to enter the license key you might have to force Windows by pressing the Windows+Pause key combination. In the lower part of the appearing window you can enter your license key and finally finish the installation and activation of your Windows “Upgrade” installation.