The Visual Studio 2008 environment(on Windows Xp) has some variables set in already WindowsSdkDir and VCInstallDir etc.. I want to setup portable cross platform packages like Xerces here : C:\Program Files\xerces-c-windows_2000-msvc_60 and configure Visual Studio 2008 environment VC++ include and lib directories with an environment variable like XercesDir set to C:\Program Files\xerces-c-windows_2000-msvc_60 . What are steps to do that?