Microsoft Visual Studio 6.0 Usage
From Valve Developer Community
It is recommended that you upgrade to Visual C++ .NET 2003 v7.1 to build the SDK projects. However, there is a tool to convert the VC++ v7.x solution and project files to VC++ v6.x projects and workspaces. It can be found at http://www.codeproject.com/tools/prjconverter.asp.
7.1 to 7.0 solution converter can be found at http://www.codeproject.com/macro/vsconvert.asp.
You must install the Service Pack 5 update and Processor Pack update to properly compile the files (Win 2000):
http://msdn.microsoft.com/vstudio/downloads/updates/sp/vs6/sp5/default.aspx
http://msdn.microsoft.com/vstudio/downloads/tools/ppack/default.aspx
Important: The Service Pack 5 update must be installed before the Processor Pack for the updates to work properly!
VS2002 users see Compiling under VS2002.
VS2005 users see Compiling under VS2005.
