When preparing to install the final version of the .NET Framework 3.0 on a system, it is necessary to uninstall any previous beta versions that are installed. In order to make the beta uninstall process as painful as possible, we released a .NET Framework 3.0 pre-release version uninstall tool.
The information on the uninstall tool download page states that the tool will uninstall pre-release versions of the .NET Framework 3.0 as well as pre-release versions of Visual Studio 2005, SQL Server 2005 Express Edition and MSDN for Visual Studio 2005.
However, while I was investigating an issue on a colleague's machine over the weekend, I found out that this cleanup tool removes the final release of SQL Server 2005 Express Edition and SQL 2005 SP1 in addition to removing pre-release versions. The uninstall tool uses Windows Installer product codes to figure out which products to remove, and the product codes for SQL Server 2005 did not change between the pre-release versions and the final release.
Until the uninstall tool is revised to correctly handle this scenario, I wanted to post a warning to anyone who uses it - if you run the .NET Framework 3.0 pre-repease version uninstall tool on a system that has the final release of SQL Server 2005 Express Edition installed, it will remove SQL Express and you will have to re-install SQL Express after running the uninstall tool.
<update date="11/21/2006"> A customer pointed out that the .NET Framework 3.0 uninstall tool also removes the final release of MSDN. I have posted an updated warning in this new blog post </update>