The release candidate (RC) for Windows 7 is expected in May, and naturally most of the people who have dedicated a machine to testing the beta release would like to be able to install it as an upgrade. Microsoft, however, has a different plan, as it explains in a new post on its Engineering Windows 7 blog:
We’ve also learned that many of you (millions) are running Windows 7 Beta full time. You’re anxious for a refresh. You’ve installed all your applications. You’ve configured and customized the system. You would love to get the RC and quickly upgrade to it from Beta. The RC, however, is about getting breadth coverage to validate the product in real-world scenarios. As a result, we want to encourage you to revert to a Vista image and upgrade or to do a clean install, rather than upgrade the existing Beta. We know that means reinstalling, recustomizing, reconfiguring, and so on. That is a real pain. The reality is that upgrading from one pre-release build to another is not a scenario we want to focus on because it is not something real-world customers will experience.
That argument makes sense, but it isn’t necessarily going to appeal to every beta tester. Case in point: myself. Since my test install of Windows 7 has never managed to send any telemetry or bug reports whatsoever to Microsoft — and Redmond’s finest could offer no advice whatsoever on how to fix that problem — reverting to Vista wouldn’t be any use to the techies, and would be a total pain for me. So I won’t be going there.
Fortunately, Microsoft does offer a workaround that will allow an in-place upgrade when the RC emerges, though it comes with plenty of stern warnings about possible issues. Here’s the main steps (hit the link for all the details):
- Download the RC ISO and burn to a DVD.
- Copy that burnt image to an external drive or a spare partition.
- Find the sources directory, and open the file cversion.ini in your favourite text editor
- To quote directly from Microsoft: “Modify the MinClient build number to a value lower than the down-level build. For example, change 7100 to 7000.”
- Save the file, and then run setup as normal to start installation.
The post also reconfirms that users running Windows XP won’t be able to upgrade in place, but will have to export settings and files before starting a clean install. To be fair, that’s still probably going to be less trouble than migrating from XP to Vista, which is theoretically supported but in practice always proved to be a hopelessly compromised experience.
Delivering a quality upgrade experience [Engineering Windows 7 Blog]