For some reason, we used "vc_x64_lib" as the output directory for the libraries, but "vc_mswu_x64" as the output directory for the samples. Place the arch suffix, i.e. "_x64" part, always after the compiler prefix (possibly including version), for consistency with both the library output directories and with MSBuild project files, as build/msw/wx_setup.props uses $(wxCompilerPrefix)$(wxArchSuffix)_... as wxIntRootDir value.