In VC, I had to add "WS2_32.lib" to the linker dependencies ( Project>Properties>Linker>Input).
This removed errors like
"...error LNK2028: unresolved token (0A000024) "extern "C" int __stdcall WSAStartup(..."
Add the library to the dependencies in "corewin_express.vsprops".
See also VC's help, "How to: Use Visual C++ Express Edition with the Microsoft
Platform SDK".