diff --git a/configure.in b/configure.in
index f4e0fea704..92b7acbeba 100644
--- a/configure.in
+++ b/configure.in
@@ -796,7 +796,6 @@ AC_CHECK_TYPES([struct in6_addr, struct sockaddr_in6, sa_family_t], , ,
 #include <sys/socket.h>
 #endif
 #ifdef _WIN32
-#define WIN32_WINNT 0x400
 #define _WIN32_WINNT 0x400
 #define WIN32_LEAN_AND_MEAN
 #if defined(_MSC_VER) && (_MSC_VER < 1300)
@@ -821,7 +820,6 @@ AC_CHECK_MEMBERS([struct in6_addr.s6_addr32, struct in6_addr.s6_addr16, struct s
 #include <sys/socket.h>
 #endif
 #ifdef _WIN32
-#define WIN32_WINNT 0x400
 #define _WIN32_WINNT 0x400
 #define WIN32_LEAN_AND_MEAN
 #if defined(_MSC_VER) && (_MSC_VER < 1300)
diff --git a/src/common/aes.c b/src/common/aes.c
index a9a018851b..692f1bca92 100644
--- a/src/common/aes.c
+++ b/src/common/aes.c
@@ -12,9 +12,6 @@
 #include "orconfig.h"
 
 #ifdef _WIN32 /*wrkard for dtls1.h >= 0.9.8m of "#include <winsock.h>"*/
- #ifndef WIN32_WINNT
- #define WIN32_WINNT 0x400
- #endif
  #ifndef _WIN32_WINNT
  #define _WIN32_WINNT 0x400
  #endif
diff --git a/src/common/compat.h b/src/common/compat.h
index 65e6cb49e0..f17aa0524e 100644
--- a/src/common/compat.h
+++ b/src/common/compat.h
@@ -9,9 +9,6 @@
 #include "orconfig.h"
 #include "torint.h"
 #ifdef _WIN32
-#ifndef WIN32_WINNT
-#define WIN32_WINNT 0x400
-#endif
 #ifndef _WIN32_WINNT
 #define _WIN32_WINNT 0x400
 #endif
diff --git a/src/common/crypto.c b/src/common/crypto.c
index e37b282757..8b1c9a658e 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -13,9 +13,6 @@
 #include "orconfig.h"
 
 #ifdef _WIN32
-#ifndef WIN32_WINNT
-#define WIN32_WINNT 0x400
-#endif
 #ifndef _WIN32_WINNT
 #define _WIN32_WINNT 0x400
 #endif
diff --git a/src/common/tortls.c b/src/common/tortls.c
index 12d982defb..180efa61db 100644
--- a/src/common/tortls.c
+++ b/src/common/tortls.c
@@ -22,9 +22,6 @@
 
 #include <assert.h>
 #ifdef _WIN32 /*wrkard for dtls1.h >= 0.9.8m of "#include <winsock.h>"*/
- #ifndef WIN32_WINNT
- #define WIN32_WINNT 0x400
- #endif
  #ifndef _WIN32_WINNT
  #define _WIN32_WINNT 0x400
  #endif
diff --git a/src/or/or.h b/src/or/or.h
index b8fee649ea..ad0ac6d021 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -23,9 +23,6 @@
 #endif
 
 #ifdef _WIN32
-#ifndef WIN32_WINNT
-#define WIN32_WINNT 0x400
-#endif
 #ifndef _WIN32_WINNT
 #define _WIN32_WINNT 0x400
 #endif