STM.NET and .NET Framework 4.0 beta 2 ( Error 1603: A fatal error occurred. )

by Koen Metsu

Recently I ran into some problems installing the latest Visual Studio 2010 beta 2. It gave me the very clear error message:

"Error 1603: A fatal error occurred."

Well that about says it all, right...?

After a lot of googling and frustration, it seemed that my previous installation of STM.NET caused this error.

I should have remembered that  "the STM enabled version of Microsoft .NET version 4.0 and official versions of .NET
version 4.0 are mutually exclusive, and cannot be installed simultaneously on the same computer".

Uninstalling STM.NET was not as easy as I thought. I assumed the almighty internet would have answers, but no dice. I spent  about a day and a half of trying almost everything : .NET Framework Cleanup tools, uninstalling anything with '.NET or 'Visual' in it's name, registry cleaning, manually removing folders from the Windows folder  ( I got desperate ).

Finally, I found the answer, thanks to an old Microsoft Support article.

  1. Go to : Start > Run > type 'Installer', press enter
  2. Right click on the column header and add the 'Comments' column
  3. Sort alphabetically and search for 'Microsoft .NET Framework 4 Client Profile Beta 1 enabled to use Software Transactional Memory...'
  4. Right-click and uninstall!
  5. Reboot ... just in case =)

This should enable you to succesfully install the 'regular' .NET Framework 4 Beta 2 and enjoy the new Visual Studio 2010 Beta!