diff --git a/include/ompi_config_bottom.h b/include/ompi_config_bottom.h
index b6a1585913..06ad1dc948 100644
--- a/include/ompi_config_bottom.h
+++ b/include/ompi_config_bottom.h
@@ -133,7 +133,7 @@ typedef struct {
  *
  **********************************************************************/
 
-#if defined(WIN32)
+#if defined(_WIN32)
 #  if OMPI_BUILDING
 #    include "win32/win_compat.h"
 #  endif
@@ -180,7 +180,7 @@ typedef struct {
                 assumption that the C++ bool is the same size and has
                 the same alignment. */
 #            include <stdbool.h>
-#        elif defined(WIN32)
+#        elif defined(_WIN32)
 #            define bool BOOL
 #            define false FALSE
 #            define true TRUE
diff --git a/ompi/include/ompi_socket_errno.h b/ompi/include/ompi_socket_errno.h
index 6449d799ac..2f6f59bd7b 100644
--- a/ompi/include/ompi_socket_errno.h
+++ b/ompi/include/ompi_socket_errno.h
@@ -29,7 +29,7 @@
 
 #include <errno.h>
 #include "ompi/include/constants.h"
-#ifdef WIN32
+#ifdef _WIN32
 #define ompi_socket_errno ompi_get_socket_errno()
 
 #define EWOULDBLOCK       WSAEWOULDBLOCK       
diff --git a/ompi/include/types.h b/ompi/include/types.h
index f171967d4c..a8656ddd85 100644
--- a/ompi/include/types.h
+++ b/ompi/include/types.h
@@ -31,7 +31,7 @@
 #include <sys/select.h>
 #endif
 
-#ifndef WIN32
+#ifndef _WIN32
 /*
  *  Increase FD_SETSIZE
  */
@@ -48,7 +48,7 @@
 #endif
 
 struct ompi_fd_set_t {
-  int i;
+    int i;
     uint32_t fds_bits[OMPI_FD_SETSIZE / NFDBITS];
 };
 typedef struct ompi_fd_set_t ompi_fd_set_t;
@@ -59,7 +59,7 @@ typedef struct ompi_fd_set_t ompi_fd_set_t;
 #define OMPI_FD_ISSET(fd,fds) FD_ISSET((fd),(fd_set*)(fds))
 
 #else /* if we are on windows */
-    
+#include <Winsock2.h>    
 typedef fd_set ompi_fd_set_t;
 #define OMPI_FD_ZERO(fds)     FD_ZERO((fds))
 #define OMPI_FD_SET(fd,fds)   FD_SET((fd),(fds))
@@ -93,7 +93,7 @@ typedef union {
  * handle differences in iovec
  */
 
-#if defined(__APPLE__) || defined(WIN32)
+#if defined(__APPLE__) || defined(_WIN32)
 typedef char* ompi_iov_base_ptr_t;
 #else
 typedef void* ompi_iov_base_ptr_t;