http://blogs.msdn.com/b/wndp/archive/2006/04/07/571105.aspxAs you may have noticed in the recent Vista CTP SDK, the Winsock headers have undergone some changes. First, instead of a couple monolithic files (winsock2.h and mswsock.h), they have been split into a number of smaller files for ease of maintenance asen-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)