How To Upgrade From Windows 7 Beta or RC to Windows 7 RTM

If you have installed Windows 7 Release Candidate or Windows 7 Beta (or any other pre-releases for that matter) then you cannot directly upgrade to Windows 7 RTM (current build: 7600.16385). Well actually you can, but after applying a trick. When trying to upgrade to Windows 7 build 7600.16385, the setup will give you an error message saying: You cannot upgrade this prerelease version of Windows 7. Go online to see how to install Windows 7 and keep your files and settings:

That's because Windows 7 RTM was build to block all versions prior to 7233. But you can bypass this by following the simple steps below:

1. Extract the contents of Windows 7 RTM ISO Image to any folder or USB Disk using WinRAR.
2. Open the sources folder, and then using notepad, open "cversion.ini" file.
3. Modify the "MinClient" build number to a value lower than the down-level build. For example, change 7233 to 7000.
Original content of cversion.ini:

[HostBuild]
MinClient=7233.0
MinServer=7100.0

How the file should look like after you have modified it:

[HostBuild]
MinClient=7000.0
MinServer=7100.0

4. Save the updated file to the same location and then run setup.exe to start Windows 7 RC upgrade process.
5. On the Installation type screen, choose whether you want to upgrade your current Windows 7 Beta or RC: