Upgrading Windows 7 Home Premium to Enterprise

I got Hannah a new laptop which came with the rather long-in-the-tooth XP installed. I had already bought and installed Windows 7 Home Premium on my work laptop. I wanted to move the Home Premium license to the new laptop. Then I wanted to upgrade my work laptop to Windows 7 Enterprise which is offered by my workplace.

Sounds simple (and legal, right?). Unfortunately:

• Windows 7 Home Premium refused to activate after doing a clean install on the new laptop citing not being an upgrade (as I had wiped XP first).
• Windows 7 Enterprise would refuse to do an upgrade from Windows 7 Home Premium, insisting on a clean install.

I found a way round both these problems which I share in case it helps anyone else. Activating Windows 7 was easy enough, simply use the phone activation wizard, call Microsoft’s toll-free number and enter in the 8 sets of digits to receive an activation code.

Upgrading from Home Premium was possible, but I had to make the following registry changes first:

Under ComputerHKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersion modify the following keys:

• EditionID from “HomePremium” to “Enterprise”.
• ProductName from “Windows 7 HomePremium” to “Enterprise”.

After doing this and running the Windows 7 installer, the upgrade process worked fine first time.

Despite the installation issues I find Windows 7 to be a huge leap forward for Microsoft operating systems. Remarkably stable, responsive, and with a pleasing user interface. My Lenovo T60 used to blue screen intermittently but this has stopped happening since installing Windows 7.