I have heard from a few folks who have run into issues trying to install and run Visual Studio on the Windows Media Center 2005 OS. One of the most common errors reported in this scenario is the following:
The application for project '<project_name>.csproj' is not installed. Make sure the application for the project type (.csproj) is installed.
This error will occur when trying to create or open a C# project in the Visual Studio IDE. When I looked into this further on one customer's machine, I found that the root cause was similar to an issue I wrote about in this previous blog post. In this scenario, the underlying problem occured when upgrading a system with Media Center 2004 and the .NET Framework 1.1 installed to Media Center 2005. This upgrade scenario will cause %windir%\system32\mscoree.dll to be reverted from the .NET Framework 1.1 version to the .NET Framework 1.0 version, which breaks a lot of functionality that depends on the .NET Framework 1.1.
If you run into this error when using the Visual Studio IDE, I suggest trying the workaround described in this blog post to uninstall and reinstall the version of the .NET Framework that is associated with the version of Visual Studio that you are using (.NET Framework 1.0 for Visual Studio .NET 2002, .NET Framework 1.1 for Visual Studio .NET 2003, or .NET Framework 2.0 for Visual Studio 2005).
Please note that although I have described an upgrade scenario that will only happen on the Windows Media Center OS, this error could also happen on a non-Media Center OS as well. The workaround has proven helpful in resolving this error in non-Media Center OS scenarios as well, so I suggest you try it if you run into it on a non-Media Center OS too.