Today I tried to install the Service Manager Authoring Tool on a couple of different machines. The pre-req check always said that Microsoft Visual Studio Shell 2008 was not installed, but I was sure I did install it. I followed the download link in the Authroing Tool setup and downloaded vs_AppEnvRedistand then I ran that file. After a while I read on this blog about an unsupported modification to skip that pre-check. If I did that unsupported modification the pre-req check did not complain about Visual Studio Shell anymore, but the installation wizard crashed during installation. I then found out that just downloading Visual Studio Shell (vs_AppEnvRedist) and run it did not install it, only extract it to in my example D:\VS 2008 Shell Redist. What we need to do is to browse to that folder and run vs_shell_isolated.enu which actually installed the Visual Studio Shell. After that I could pass both the pre-req check finish eh installation successfully.