diff --git a/src/mzscheme/src/network.c b/src/mzscheme/src/network.c
index d8d8db2b26..2c0e163e35 100644
--- a/src/mzscheme/src/network.c
+++ b/src/mzscheme/src/network.c
@@ -78,6 +78,7 @@ static int mzerrno = 0;
 # include <process.h>
 # include <winsock2.h>
 # include <ws2tcpip.h>
+# include <wspiapi.h>
 struct SOCKADDR_IN {
   short sin_family;
   unsigned short sin_port;