How to Upgrade the Windows 7 RC to RTM (Final Release)

By Lowell Heddings on August 6th, 2009

The final version of Windows 7 was released yesterday for MS Technet subscribers, but you can’t upgrade directly from a pre-release version—at least, not without a quick and easy workaround, and we’ve got you covered.

The Problem

Windows 7 checks whether or not the current version you are running is a pre-release copy, and prevents you from upgrading further. For reference purposes, this is the error you’ll see when you try and upgrade.

Windows 7 can't upgrade error

The Solution

The solution is to edit a file inside the Windows 7 DVD—which you’ll have to extract to the hard drive to proceed.

  • If you are using an ISO image for the installation progress, you can use the awesome 7-Zip utility to extract the ISO to a folder on the drive.
  • If you are using an actual DVD, you can simply copy all of the files from the DVD to a folder on your hard drive.

Once you’ve extract the files, browse down into the “sources” folder to find the cversion.ini file.

Windows 7 CD files

Once you’ve opened up the cversion.ini file, you’ll notice that the MinClient line has a value of 7233.0, and since the Windows 7 RC release is build 7100, you can understand why it’s not working.

Editing cversion file

All you need to do is change the MinClient value to something less than the current build you are using. For the RC release, you can change it to 7000.

Editing cversion file 

Now you can simply launch the setup.exe file from within the folder, and do the upgrade directly from the hard drive. Once you’ve started the setup, click Install now.

Windows 7 upgrade startup

Once you get to the type of installation screen, choose to Upgrade the existing install.

Windows 7 choose upgrade type

Once you reach the Compatibility Report screen (if it doesn’t show up at all, be happy about it), you’ll see the list of applications that probably won’t work once you upgrade. Realistically most of these apps will work just fine, but the important thing is that you’ll be able to upgrade.

Note: You could always smooth the upgrade process by removing any apps that have compatibility problems, before you do the upgrade.

Windows 7 upgrade compatibility report

At this point, the upgrade should start working, and will take a rather long time.

Windows 7 is upgrading just fine 

Important Notes

There are a few important things to keep in mind when you are upgrading to the final version:

  • The Windows 7 beta or RC releases were Ultimate edition, so you’ll only be able to upgrade to the RTM (final) if you are installing Ultimate Edition.
  • Whenever possible, you should really backup your files and do a clean install. There are less headaches this way, and you get the benefit of a nice clean profile.

Happy upgrading!

What’s Next?

We’ve got well over 100 articles covering how to use, tweak, and optimize your Windows 7 experience. Just head over to the Windows 7 category page:

Click Here for 175+ More Windows 7 Articles

Lowell Heddings, better known online as the How-To Geek, spends all his free time bringing you fresh geekery on a daily basis. You can follow him on if you'd like.

  • Published 08/6/09
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