diff --git a/compat/mingw.h b/compat/mingw.h
index 8848c7bc2c..389ae0164f 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -1,3 +1,4 @@
+#define _WIN32_WINNT 0x0501
 #include <winsock2.h>
 #include <ws2tcpip.h>
 
diff --git a/git-compat-util.h b/git-compat-util.h
index 9d297b498a..43a5b50573 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -86,6 +86,7 @@
 #define _SGI_SOURCE 1
 
 #ifdef WIN32 /* Both MinGW and MSVC */
+#define _WIN32_WINNT 0x0501
 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 #include <winsock2.h>
 #include <windows.h>