Random Ramblings

A few weeks back I was given the task of upgrading my girlfriend’s laptop from Vista Home Premium to Windows 7 Professional. Traditionally I like to do a clean format when changing OS. You just never know what rubbish can creep into the new install.

One piece of software that she has (Sibelius I’m looking at you) can be a bit of a pain to get licensed, and not wanting to lose any of her work files, I decided to investigate the in-place upgrade. I had heard that performing an in-place upgrade was smooth and relatively pain-free, if not lengthy, so I was optimistic that it wouldn’t be a problem, but was still cautious. Another hitch is the fact that Microsoft, in their infinite wisdom, does not allow you to perform an in-place upgrade from Vista Home Premium (or for that matter Home Basic) to Windows 7 Professional. That is, not without a little trick that I’ll explain a bit further down.

As a precaution, I took a backup of all of the files and settings in Vista using the Windows Easy Transfer software provided on the Windows 7 DVD. I left this going overnight as there were near on 20 Gb worth of files to backup. As the program title says, this was easy. In the meantime I set up a VM, installed Vista Home Premium so that I can test the trick I found. I didn’t want to go stuffing anything up and leaving an unworkable system. The trick worked without any hitch at all so I was confident that the real upgrade will proceed without an issue.

So here’s the deal. I doubt that this is against the license agreement, since the end result is still a legally acquired upgrade DVD installed on a laptop that has a legally acquired OS, and has the same net effect of performing a custom install and all applications and files transferred onto the new OS. Having said that, don’t shoot me if that assumption turns out to be incorrect. Note also that you will have to modify the registry to perform this trick, so if you go editing something else that’s on you if things go crazy.

The Windows 7 Setup only checks two registry values to see what edition of Vista is running on the computer, in order to determine whether to perform an in-place upgrade or to stop you and tell you to go perform a clean/custom install. The values are:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion, EditionID; and
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion, ProductName

For Vista Home Premium, the EditionID value will be HomePremium and ProductName will be Windows Vista Home Premium. You need to change them to Business and Windows Vista Business respectively. And there you have it. Windows 7 Setup will upgrade your OS to Windows 7 Professional. You could possibly change these values to upgrade to a lower edition of Windows 7, but whether that viloates the license agreement is yet to be determined.

Back to my experience…
Thanks to the laptop manufacturer, instructions were provided as to how best to perform an upgrade with the included applications. There were a few items to uninstall pre-upgrade which were thankfully not too difficult. A reboot or two later and I was ready to modify the registry and perform the upgrade. As confirmed on the VM, the trick worked and Windows 7 Setup started the upgrade.

I believe what happens is Setup takes a backup of all of the files in Program Files and Users, performs almost a clean install, then restores the files to their original location. The in-place upgrade took about 3-4 hours, so be prepared. Once the upgrade was done I installed the Windows 7 drivers provided by the laptop manufacturer and crossed my fingers as my girlfriend checked it out to make sure nothing was lost and that everything else works as expected. Luckily, it did.

All in all, this adds to my belief that Microsoft have released their best OS by far in Windows 7. The setup process (for both a clean install and an upgrade) is easy and seemless, the interface changes between Vista and 7 work much better and actually make sense, and it performs like a dream. If you’re about to upgrade from Vista to 7, don’t fret too much. Take a backup, just in case, and let Setup work it’s magic. You’ll thank yourself for it.