diff --git a/applications/present3D/Cluster.cpp b/applications/present3D/Cluster.cpp
index 86785b1c6..4dc9c4f24 100644
--- a/applications/present3D/Cluster.cpp
+++ b/applications/present3D/Cluster.cpp
@@ -18,7 +18,7 @@
 #include <sys/types.h>
 #include <errno.h>
 
-#if !defined (WIN32) || defined(__CYGWIN__)
+#if !defined (_WIN32) || defined(__CYGWIN__)
 #include <sys/ioctl.h>
 #include <sys/uio.h>
 #include <sys/socket.h>
@@ -51,7 +51,7 @@
 #elif defined (__APPLE__)
     #include <unistd.h>
     #include <sys/sockio.h>
-#elif defined (WIN32)
+#elif defined (_WIN32)
     #include <winsock.h>
     #include <stdio.h>
 #elif defined (__hpux)
@@ -63,7 +63,7 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <sys/types.h>
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 #include <winsock.h>
 #else
 #include <unistd.h>
@@ -265,7 +265,7 @@ Receiver::Receiver( void )
 
 Receiver::~Receiver( void )
 {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     closesocket( _so);
 #else
     close( _so );
@@ -274,7 +274,7 @@ Receiver::~Receiver( void )
 
 bool Receiver::init( void )
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     WORD version = MAKEWORD(1,1);
     WSADATA wsaData;
     // First, we start up Winsock
@@ -295,7 +295,7 @@ bool Receiver::init( void )
 
     int result = 0;
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 //    const BOOL on = TRUE;
 //    setsockopt( _so, SOL_SOCKET, SO_REUSEADDR, (const char*) &on, sizeof(int));
 #else
@@ -312,7 +312,7 @@ bool Receiver::init( void )
 //    struct sockaddr_in saddr;
     saddr.sin_family = AF_INET;
     saddr.sin_port   = htons( _port );
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     saddr.sin_addr.s_addr =  htonl(INADDR_ANY);
 #else
     saddr.sin_addr.s_addr =  0;
@@ -366,7 +366,7 @@ void Receiver::sync( void )
     tv.tv_sec = 0;
     tv.tv_usec = 0;
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 //    saddr.sin_port   = htons( _port );
     int result = recvfrom( _so, (char *)_buffer, _buffer_size, 0, (sockaddr*)&saddr, &size );
 //    recvfrom(sock_Receive, szMessage, 256, 0, (sockaddr*)&addr_Cli, &clilen)
@@ -419,7 +419,7 @@ Broadcaster::Broadcaster( void )
 
 Broadcaster::~Broadcaster( void )
 {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     closesocket( _so);
 #else
     close( _so );
@@ -428,7 +428,7 @@ Broadcaster::~Broadcaster( void )
 
 bool Broadcaster::init( void )
 {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     WORD version = MAKEWORD(1,1);
     WSADATA wsaData;
     // First, we start up Winsock
@@ -446,7 +446,7 @@ bool Broadcaster::init( void )
         perror( "Socket" );
         return false;
     }
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     const BOOL on = TRUE;
 #else
     int on = 1;
@@ -454,7 +454,7 @@ bool Broadcaster::init( void )
 
     int result = 0;
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     result = setsockopt( _so, SOL_SOCKET, SO_REUSEADDR, (const char *) &on, sizeof(int));
 #else
     result = setsockopt( _so, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
@@ -466,24 +466,24 @@ bool Broadcaster::init( void )
     saddr.sin_port   = htons( _port );
     if( _address == 0 )
     {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
         result = setsockopt( _so, SOL_SOCKET, SO_BROADCAST, (const char *) &on, sizeof(int));
 #else
         result = setsockopt( _so, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on));
 #endif
         if (result) return false;
 
-#if !defined (WIN32) || defined(__CYGWIN__)
+#if !defined (_WIN32) || defined(__CYGWIN__)
         struct ifreq ifr;
 #endif
 #if defined (__linux) || defined(__CYGWIN__)
         strcpy( ifr.ifr_name, "eth0" );
 #elif defined(__sun)
         strcpy( ifr.ifr_name, "hme0" );
-#elif !defined (WIN32)
+#elif !defined (_WIN32)
         strcpy( ifr.ifr_name, "ef0" );
 #endif
-#if defined (WIN32) // get the server address
+#if defined (_WIN32) // get the server address
         saddr.sin_addr.s_addr = htonl(INADDR_BROADCAST);
     }
 #else
@@ -543,7 +543,7 @@ void Broadcaster::sync( void )
     }
 
     int result = 0;
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     unsigned int size = sizeof( SOCKADDR_IN );
     result = sendto( _so, (const char *)_buffer, _buffer_size, 0, (struct sockaddr *)&saddr, size );
     // int err = WSAGetLastError ();
diff --git a/applications/present3D/Cluster.h b/applications/present3D/Cluster.h
index f594d9c52..6c25c2c2c 100644
--- a/applications/present3D/Cluster.h
+++ b/applications/present3D/Cluster.h
@@ -19,7 +19,7 @@
 
 #include <osgViewer/Viewer>
 
-#if !defined(WIN32) || defined(__CYGWIN__)
+#if !defined(_WIN32) || defined(__CYGWIN__)
     #include <netinet/in.h>
 #else
     #include "winsock.h"
@@ -51,7 +51,7 @@ class Receiver
     bool init( void );
 
     private :
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
         SOCKET _so;
         SOCKADDR_IN saddr;
 #else
@@ -94,7 +94,7 @@ class Broadcaster
     bool init( void );
 
     private :
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
         SOCKET _so;
 #else
         int _so;
@@ -103,7 +103,7 @@ class Broadcaster
         short _port;
         void *_buffer;
         unsigned int _buffer_size;
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
         SOCKADDR_IN saddr;
 #else
         struct sockaddr_in saddr;
diff --git a/examples/osgcluster/broadcaster.cpp b/examples/osgcluster/broadcaster.cpp
index a1a21432f..d968f4372 100644
--- a/examples/osgcluster/broadcaster.cpp
+++ b/examples/osgcluster/broadcaster.cpp
@@ -21,7 +21,7 @@
 #include <sys/types.h>
 #include <iostream>
 
-#if !defined (WIN32) || defined(__CYGWIN__)
+#if !defined (_WIN32) || defined(__CYGWIN__)
 #include <sys/ioctl.h>
 #include <sys/uio.h>
 #include <sys/socket.h>
@@ -54,7 +54,7 @@
 #elif defined (__APPLE__)
     #include <unistd.h>
     #include <sys/sockio.h>
-#elif defined (WIN32)
+#elif defined (_WIN32)
     #include <winsock.h>
     #include <stdio.h>
 #elif defined (__hpux)
@@ -73,7 +73,7 @@ Broadcaster::Broadcaster( void )
      _ifr_name = "eth0";
 #elif defined(__sun)
      _ifr_name = "hme0";
-#elif !defined (WIN32)
+#elif !defined (_WIN32)
      _ifr_name = "ef0";
 #endif
     _port = 0;
@@ -84,7 +84,7 @@ Broadcaster::Broadcaster( void )
 
 Broadcaster::~Broadcaster( void )
 {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     closesocket( _so);
 #else
     close( _so );
@@ -93,7 +93,7 @@ Broadcaster::~Broadcaster( void )
 
 bool Broadcaster::init( void )
 {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     WORD version = MAKEWORD(1,1);
     WSADATA wsaData;
     // First, we start up Winsock
@@ -111,13 +111,13 @@ bool Broadcaster::init( void )
         perror( "Socket" );
         return false;
     }
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     const BOOL on = TRUE;
 #else
     int on = 1;
 #endif
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     setsockopt( _so, SOL_SOCKET, SO_REUSEADDR, (const char *) &on, sizeof(int));
 #else
     setsockopt( _so, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
@@ -127,17 +127,17 @@ bool Broadcaster::init( void )
     saddr.sin_port   = htons( _port );
     if( _address == 0 )
     {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
         setsockopt( _so, SOL_SOCKET, SO_BROADCAST, (const char *) &on, sizeof(int));
 #else
         setsockopt( _so, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on));
 #endif
 
-#if !defined (WIN32) || defined(__CYGWIN__)
+#if !defined (_WIN32) || defined(__CYGWIN__)
         struct ifreq ifr;
         strcpy( ifr.ifr_name, _ifr_name.c_str());
 #endif
-#if defined (WIN32) // get the server address
+#if defined (_WIN32) // get the server address
         saddr.sin_addr.s_addr = htonl(INADDR_BROADCAST);
     }
 #else
@@ -202,7 +202,7 @@ void Broadcaster::sync( void )
         return;
     }
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     unsigned int size = sizeof( SOCKADDR_IN );
     sendto( _so, (const char *)_buffer, _buffer_size, 0, (struct sockaddr *)&saddr, size );
     int err = WSAGetLastError ();
diff --git a/examples/osgcluster/broadcaster.h b/examples/osgcluster/broadcaster.h
index 8f9648cb3..bcdd68aa2 100644
--- a/examples/osgcluster/broadcaster.h
+++ b/examples/osgcluster/broadcaster.h
@@ -29,7 +29,7 @@
 // Class definition for broadcasting a buffer to a LAN
 //
 
-#if !defined(WIN32) || defined(__CYGWIN__)
+#if !defined(_WIN32) || defined(__CYGWIN__)
     #include <netinet/in.h>
 #endif
 
@@ -65,7 +65,7 @@ class Broadcaster
 
         std::string _ifr_name;
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
         SOCKET _so;
 #else
         int _so;
@@ -74,7 +74,7 @@ class Broadcaster
         short _port;
         void *_buffer;
         unsigned int _buffer_size;
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
         SOCKADDR_IN saddr;
 #else
         struct sockaddr_in saddr;
diff --git a/examples/osgcluster/osgcluster.cpp b/examples/osgcluster/osgcluster.cpp
index 832e09290..e2ba41d7a 100644
--- a/examples/osgcluster/osgcluster.cpp
+++ b/examples/osgcluster/osgcluster.cpp
@@ -36,7 +36,7 @@
 
 #include <iostream>
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 #include <winsock.h>
 #endif
 
diff --git a/examples/osgcluster/receiver.cpp b/examples/osgcluster/receiver.cpp
index 6ab5e7931..985fab4e5 100644
--- a/examples/osgcluster/receiver.cpp
+++ b/examples/osgcluster/receiver.cpp
@@ -19,7 +19,7 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <sys/types.h>
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 #include <winsock.h>
 #else
 #include <unistd.h>
@@ -46,7 +46,7 @@ Receiver::Receiver( void )
 
 Receiver::~Receiver( void )
 {
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     closesocket( _so);
 #else
     close( _so );
@@ -55,7 +55,7 @@ Receiver::~Receiver( void )
 
 bool Receiver::init( void )
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     WORD version = MAKEWORD(1,1);
     WSADATA wsaData;
     // First, we start up Winsock
@@ -73,7 +73,7 @@ bool Receiver::init( void )
         perror( "Socket" );
     return false;
     }
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 //    const BOOL on = TRUE;
 //    setsockopt( _so, SOL_SOCKET, SO_REUSEADDR, (const char*) &on, sizeof(int));
 #else
@@ -84,7 +84,7 @@ bool Receiver::init( void )
 //    struct sockaddr_in saddr;
     saddr.sin_family = AF_INET;
     saddr.sin_port   = htons( _port );
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
     saddr.sin_addr.s_addr =  htonl(INADDR_ANY);
 #else
     saddr.sin_addr.s_addr =  0;
@@ -137,7 +137,7 @@ unsigned int Receiver::sync( void )
     tv.tv_sec = 0;
     tv.tv_usec = 0;
 
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
 //    saddr.sin_port   = htons( _port );
     recvfrom( _so, (char *)_buffer, _buffer_size, 0, (sockaddr*)&saddr, &size );
 //    recvfrom(sock_Receive, szMessage, 256, 0, (sockaddr*)&addr_Cli, &clilen)
diff --git a/examples/osgcluster/receiver.h b/examples/osgcluster/receiver.h
index 7b2a3b5d5..3d4877cff 100644
--- a/examples/osgcluster/receiver.h
+++ b/examples/osgcluster/receiver.h
@@ -28,7 +28,7 @@
 // Class definition for the recipient of a broadcasted message
 //
 
-#if !defined(WIN32) || defined(__CYGWIN__)
+#if !defined(_WIN32) || defined(__CYGWIN__)
     #include <netinet/in.h>
 #endif
 
@@ -53,7 +53,7 @@ class Receiver
 	bool init( void );
 
     private :
-#if defined (WIN32) && !defined(__CYGWIN__)
+#if defined (_WIN32) && !defined(__CYGWIN__)
         SOCKET _so;
         SOCKADDR_IN saddr;
 #else
diff --git a/examples/osghangglide/terrain_coords.h b/examples/osghangglide/terrain_coords.h
index 04aad2fd2..948c003d4 100644
--- a/examples/osghangglide/terrain_coords.h
+++ b/examples/osghangglide/terrain_coords.h
@@ -18,7 +18,7 @@
 *  THE SOFTWARE.
 */
 
-#if defined(WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
     // disable the double to float errors.
     #pragma warning( disable : 4305 )
 #endif
diff --git a/examples/osghangglide/terrain_normals.h b/examples/osghangglide/terrain_normals.h
index bfe1dc705..081f5c96f 100644
--- a/examples/osghangglide/terrain_normals.h
+++ b/examples/osghangglide/terrain_normals.h
@@ -18,7 +18,7 @@
 *  THE SOFTWARE.
 */
 
-#if defined(WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
     // disable the double to float errors.
     #pragma warning( disable : 4305 )
 #endif
diff --git a/examples/osghangglide/terrain_texcoords.h b/examples/osghangglide/terrain_texcoords.h
index 33cd35149..adc4c822f 100644
--- a/examples/osghangglide/terrain_texcoords.h
+++ b/examples/osghangglide/terrain_texcoords.h
@@ -18,7 +18,7 @@
 *  THE SOFTWARE.
 */
 
-#if defined(WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
     // disable the double to float errors.
     #pragma warning( disable : 4305 )
 #endif
diff --git a/examples/osgmovie/osgmovie.cpp b/examples/osgmovie/osgmovie.cpp
index 9de15b188..33775af9a 100644
--- a/examples/osgmovie/osgmovie.cpp
+++ b/examples/osgmovie/osgmovie.cpp
@@ -417,7 +417,7 @@ int main(int argc, char** argv)
     arguments.getApplicationUsage()->addCommandLineOption("--shader","Use shaders to post process the video.");
     arguments.getApplicationUsage()->addCommandLineOption("--interactive","Use camera manipulator to allow movement around movie.");
     arguments.getApplicationUsage()->addCommandLineOption("--flip","Flip the movie so top becomes bottom.");
-#if defined(WIN32) || defined(__APPLE__)
+#if defined(_WIN32) || defined(__APPLE__)
     arguments.getApplicationUsage()->addCommandLineOption("--devices","Print the Video input capability via QuickTime and exit.");
 #endif
 
@@ -433,7 +433,7 @@ int main(int argc, char** argv)
         return 1;
     }
 
-#if defined(WIN32) || defined(__APPLE__)
+#if defined(_WIN32) || defined(__APPLE__)
     // if user requests devices video capability.
     if (arguments.read("-devices") || arguments.read("--devices"))
     {
diff --git a/examples/osgshadow/terrain_coords.h b/examples/osgshadow/terrain_coords.h
index 04aad2fd2..948c003d4 100644
--- a/examples/osgshadow/terrain_coords.h
+++ b/examples/osgshadow/terrain_coords.h
@@ -18,7 +18,7 @@
 *  THE SOFTWARE.
 */
 
-#if defined(WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
     // disable the double to float errors.
     #pragma warning( disable : 4305 )
 #endif
diff --git a/examples/osgsimulation/osgsimulation.cpp b/examples/osgsimulation/osgsimulation.cpp
index c5509b43a..dd114e2fb 100644
--- a/examples/osgsimulation/osgsimulation.cpp
+++ b/examples/osgsimulation/osgsimulation.cpp
@@ -16,7 +16,7 @@
 *  THE SOFTWARE.
 */
 
-#if defined(WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
 /////////////////////////////////////////////////////////////////////////////
 // Disable unavoidable warning messages:
 
@@ -32,7 +32,7 @@
 
 #pragma warning(disable : 4103 4114 4201 4237 4251 4275 4290 4503 4335 4786)
 
-#endif // WIN32
+#endif // _WIN32
 
 #include <osgViewer/Viewer>
 #include <osgViewer/ViewerEventHandlers>
diff --git a/examples/osgunittests/UnitTestFramework.cpp b/examples/osgunittests/UnitTestFramework.cpp
index 13305fb05..b9f88d8f9 100644
--- a/examples/osgunittests/UnitTestFramework.cpp
+++ b/examples/osgunittests/UnitTestFramework.cpp
@@ -50,7 +50,7 @@ std::ostream& TestContext::tout(TraceLevel tl) const
 TestContext::TraceStream::TraceStream(std::ostream& o, TraceLevel tl):
     _traceLevel(tl),
     _outputStreamPtr(&o),
-#if defined(WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__))
     _nullStream("nul")
 #else
     _nullStream("/dev/null")
diff --git a/examples/osgviewerWX/osgviewerWX.cpp b/examples/osgviewerWX/osgviewerWX.cpp
index 7befa2f30..d5a6aac02 100644
--- a/examples/osgviewerWX/osgviewerWX.cpp
+++ b/examples/osgviewerWX/osgviewerWX.cpp
@@ -10,7 +10,7 @@
 #endif
 
 // For wxCURSOR_BLANK below, but isn't used a.t.m.
-//#ifdef WIN32
+//#ifdef _WIN32
 //#include "wx/msw/wx.rc"
 //#endif
 
diff --git a/include/OpenThreads/Exports b/include/OpenThreads/Exports
index bf2620993..8755ce51a 100644
--- a/include/OpenThreads/Exports
+++ b/include/OpenThreads/Exports
@@ -16,7 +16,7 @@
 
 #include <OpenThreads/Config>
 
-#ifndef WIN32
+#ifndef _WIN32
     #define OPENTHREAD_EXPORT_DIRECTIVE
 #else
     #if defined( OT_LIBRARY_STATIC )
diff --git a/include/osg/Notify b/include/osg/Notify
index 9e21a8695..9bb8e684b 100644
--- a/include/osg/Notify
+++ b/include/osg/Notify
@@ -126,7 +126,7 @@ public:
     void notify(osg::NotifySeverity severity, const char *message);
 };
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 
 /** Redirects notification stream to windows debugger with use of
   * OuputDebugString functions.
diff --git a/include/osg/Timer b/include/osg/Timer
index ac1a452d1..acc3ab79f 100644
--- a/include/osg/Timer
+++ b/include/osg/Timer
@@ -18,7 +18,7 @@
 
 namespace osg {
 
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(__clang__)
     typedef unsigned __int64 Timer_t;
 #else
     typedef unsigned long long Timer_t;
diff --git a/src/osg/ArgumentParser.cpp b/src/osg/ArgumentParser.cpp
index c1fb6fca7..76ce9ac51 100644
--- a/src/osg/ArgumentParser.cpp
+++ b/src/osg/ArgumentParser.cpp
@@ -198,7 +198,7 @@ ArgumentParser::ArgumentParser(int* argc,char **argv):
     }
 #endif
 
-#ifdef WIN32
+#ifdef _WIN32
     // Remove linefeed from last argument if it exist
     char* lastline = argc==0 ? 0 : _argv[*argc-1];
     if (lastline)
diff --git a/src/osg/DisplaySettings.cpp b/src/osg/DisplaySettings.cpp
index 5c699c8b0..c65a808b1 100644
--- a/src/osg/DisplaySettings.cpp
+++ b/src/osg/DisplaySettings.cpp
@@ -25,7 +25,7 @@
 using namespace osg;
 using namespace std;
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 #include<windows.h>
 extern "C" { OSG_EXPORT DWORD NvOptimusEnablement=0x00000001; }
 #else
@@ -719,7 +719,7 @@ void DisplaySettings::readEnvironmentalVariables()
 
     if (getEnvVar("OSG_KEYSTONE_FILES", value))
     {
-    #if defined(WIN32) && !defined(__CYGWIN__)
+    #if defined(_WIN32) && !defined(__CYGWIN__)
         char delimitor = ';';
     #else
         char delimitor = ':';
diff --git a/src/osg/GL.in b/src/osg/GL.in
index 2f790be4f..e6c220318 100644
--- a/src/osg/GL.in
+++ b/src/osg/GL.in
@@ -42,7 +42,7 @@
 #define OSG_GL_CONTEXT_VERSION "@OSG_GL_CONTEXT_VERSION@"
 
 
-#ifndef WIN32
+#ifndef _WIN32
 
     // Required for compatibility with glext.h style function definitions of
     // OpenGL extensions, such as in src/osg/Point.cpp.
@@ -50,7 +50,7 @@
         #define APIENTRY
     #endif
 
-#else // WIN32
+#else // _WIN32
 
     #if defined(__CYGWIN__) || defined(__MINGW32__)
 
@@ -103,7 +103,7 @@
         #define _WCHAR_T_DEFINED
     #endif
 
-#endif // WIN32
+#endif // _WIN32
 
 #if defined(OSG_GL3_AVAILABLE)
     #define GL3_PROTOTYPES 1
diff --git a/src/osg/GLExtensions.cpp b/src/osg/GLExtensions.cpp
index 88c139c13..375ba86be 100644
--- a/src/osg/GLExtensions.cpp
+++ b/src/osg/GLExtensions.cpp
@@ -27,7 +27,7 @@
 #include <set>
 #include <sstream>
 
-#if defined(WIN32)
+#if defined(_WIN32)
     #ifndef WIN32_LEAN_AND_MEAN
         #define WIN32_LEAN_AND_MEAN
     #endif // WIN32_LEAN_AND_MEAN
@@ -174,7 +174,7 @@ bool osg::isGLExtensionOrVersionSupported(unsigned int contextID, const char *ex
                 if (*startOfWord!=0) extensionSet.insert(std::string(startOfWord));
             }
 
-    #if defined(WIN32) && (defined(OSG_GL1_AVAILABLE) || defined(OSG_GL2_AVAILABLE) || defined(OSG_GL3_AVAILABLE))
+    #if defined(_WIN32) && (defined(OSG_GL1_AVAILABLE) || defined(OSG_GL2_AVAILABLE) || defined(OSG_GL3_AVAILABLE))
 
             // add WGL extensions to the list
 
@@ -340,7 +340,7 @@ OSG_INIT_SINGLETON_PROXY(GLExtensionDisableStringInitializationProxy, osg::getGL
         #endif
         return dlsym(handle, funcName);
 
-    #elif defined(WIN32)
+    #elif defined(_WIN32)
 
         #if defined(OSG_GLES2_AVAILABLE)
             static HMODULE hmodule = GetModuleHandle(TEXT("libGLESv2.dll"));
diff --git a/src/osg/Notify.cpp b/src/osg/Notify.cpp
index c4cef6029..16c609e79 100644
--- a/src/osg/Notify.cpp
+++ b/src/osg/Notify.cpp
@@ -241,7 +241,7 @@ void osg::StandardNotifyHandler::notify(osg::NotifySeverity severity, const char
         fputs(message, stdout);
 }
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 
 #ifndef WIN32_LEAN_AND_MEAN
     #define WIN32_LEAN_AND_MEAN
diff --git a/src/osg/PagedLOD.cpp b/src/osg/PagedLOD.cpp
index e2680b2bd..461758567 100644
--- a/src/osg/PagedLOD.cpp
+++ b/src/osg/PagedLOD.cpp
@@ -98,7 +98,7 @@ void PagedLOD::setDatabasePath(const std::string& path)
 
 /*
         // make sure the last character is the appropriate slash
-#ifdef WIN32
+#ifdef _WIN32
         if (lastCharacter==unixSlash)
         {
             lastCharacter = winSlash;
diff --git a/src/osg/Timer.cpp b/src/osg/Timer.cpp
index 873e2e6c8..0fec87f05 100644
--- a/src/osg/Timer.cpp
+++ b/src/osg/Timer.cpp
@@ -20,7 +20,7 @@
 using namespace osg;
 
 // follows are the constructors of the Timer class, once version
-// for each OS combination.  The order is WIN32, FreeBSD, Linux, IRIX,
+// for each OS combination.  The order is _WIN32, FreeBSD, Linux, IRIX,
 // and the rest of the world.
 //
 // all the rest of the timer methods are implemented within the header.
@@ -32,7 +32,7 @@ Timer* Timer::instance()
     return &s_timer;
 }
 
-#ifdef WIN32
+#ifdef _WIN32
 
     #include <sys/types.h>
     #include <fcntl.h>
diff --git a/src/osgDB/ConvertUTF.cpp b/src/osgDB/ConvertUTF.cpp
index 1b5013a89..caaf3672a 100644
--- a/src/osgDB/ConvertUTF.cpp
+++ b/src/osgDB/ConvertUTF.cpp
@@ -17,7 +17,7 @@
 #include <string.h>
 #include <wchar.h>
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #endif
@@ -39,7 +39,7 @@ std::string convertStringFromUTF8toCurrentCodePage(const char* s){return convert
 
 std::string convertUTF16toUTF8(const wchar_t* source, unsigned sourceLength)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     if (sourceLength == 0)
     {
         return std::string();
@@ -71,7 +71,7 @@ std::string convertUTF16toUTF8(const wchar_t* source, unsigned sourceLength)
 
 std::wstring convertUTF8toUTF16(const char* source, unsigned sourceLength)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     if (sourceLength == 0)
     {
         return std::wstring();
@@ -103,7 +103,7 @@ std::wstring convertUTF8toUTF16(const char* source, unsigned sourceLength)
 
 std::string convertStringFromCurrentCodePageToUTF8(const char* source, unsigned sourceLength)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     if (sourceLength == 0)
     {
         return std::string();
@@ -132,7 +132,7 @@ std::string convertStringFromCurrentCodePageToUTF8(const char* source, unsigned
 
 std::string convertStringFromUTF8toCurrentCodePage(const char* source, unsigned sourceLength)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     if (sourceLength == 0)
     {
         return std::string();
diff --git a/src/osgDB/DatabasePager.cpp b/src/osgDB/DatabasePager.cpp
index 856250d1a..253231154 100644
--- a/src/osgDB/DatabasePager.cpp
+++ b/src/osgDB/DatabasePager.cpp
@@ -34,7 +34,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-#ifdef WIN32
+#ifdef _WIN32
 #include <windows.h>
 #else
 #include <unistd.h>
diff --git a/src/osgDB/DynamicLibrary.cpp b/src/osgDB/DynamicLibrary.cpp
index 913429245..c26cd4a0a 100644
--- a/src/osgDB/DynamicLibrary.cpp
+++ b/src/osgDB/DynamicLibrary.cpp
@@ -19,7 +19,7 @@
 #endif
 #endif
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 #include <io.h>
 #include <windows.h>
 #include <winbase.h>
@@ -59,7 +59,7 @@ DynamicLibrary::~DynamicLibrary()
     if (_handle)
     {
         OSG_INFO<<"Closing DynamicLibrary "<<_name<<std::endl;
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
         FreeLibrary((HMODULE)_handle);
 #elif defined(__APPLE__) && defined(APPLE_PRE_10_3)
         NSUnLinkModule(static_cast<NSModule>(_handle), FALSE);
@@ -95,7 +95,7 @@ DynamicLibrary::HANDLE DynamicLibrary::getLibraryHandle( const std::string& libr
 {
     HANDLE handle = NULL;
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 #ifdef OSG_USE_UTF8_FILENAME
     handle = LoadLibraryW(  convertUTF8toUTF16(libraryName).c_str() );
 #else
@@ -150,7 +150,7 @@ DynamicLibrary::HANDLE DynamicLibrary::getLibraryHandle( const std::string& libr
 DynamicLibrary::PROC_ADDRESS DynamicLibrary::getProcAddress(const std::string& procName)
 {
     if (_handle==NULL) return NULL;
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     return osg::convertPointerType<DynamicLibrary::PROC_ADDRESS, FARPROC>( GetProcAddress( (HMODULE)_handle, procName.c_str() ) );
 #elif defined(__APPLE__) && defined(APPLE_PRE_10_3)
     std::string temp("_");
diff --git a/src/osgDB/FileNameUtils.cpp b/src/osgDB/FileNameUtils.cpp
index ceb09ebe9..bcc59ae3b 100644
--- a/src/osgDB/FileNameUtils.cpp
+++ b/src/osgDB/FileNameUtils.cpp
@@ -18,13 +18,13 @@
 #include <osgDB/FileNameUtils>
 #include <osgDB/FileUtils>
 
-#ifdef WIN32
+#ifdef _WIN32
     #include <windows.h>
 #endif
 
 #if defined(__sgi)
     #include <ctype.h>
-#elif defined(__GNUC__) || !defined(WIN32) || defined(__MWERKS__)
+#elif defined(__GNUC__) || !defined(_WIN32) || defined(__MWERKS__)
     #include <cctype>
     using std::tolower;
 #endif
@@ -98,7 +98,7 @@ std::string osgDB::convertFileNameToUnixStyle(const std::string& fileName)
 
 char osgDB::getNativePathSeparator()
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     return WINDOWS_PATH_SEPARATOR;
 #else
     return UNIX_PATH_SEPARATOR;
@@ -107,7 +107,7 @@ char osgDB::getNativePathSeparator()
 
 bool osgDB::isFileNameNativeStyle(const std::string& fileName)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     return fileName.find(UNIX_PATH_SEPARATOR) == std::string::npos; // return true if no unix style slash exist
 #else
     return fileName.find(WINDOWS_PATH_SEPARATOR) == std::string::npos; // return true if no windows style backslash exist
@@ -116,7 +116,7 @@ bool osgDB::isFileNameNativeStyle(const std::string& fileName)
 
 std::string osgDB::convertFileNameToNativeStyle(const std::string& fileName)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     return convertFileNameToWindowsStyle(fileName);
 #else
     return convertFileNameToUnixStyle(fileName);
@@ -261,7 +261,7 @@ std::string osgDB::getServerFileName(const std::string& filename)
 
 std::string osgDB::concatPaths(const std::string& left, const std::string& right)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     const char delimiterNative  = WINDOWS_PATH_SEPARATOR;
     const char delimiterForeign = UNIX_PATH_SEPARATOR;
 #else
@@ -291,7 +291,7 @@ std::string osgDB::concatPaths(const std::string& left, const std::string& right
 
 std::string osgDB::getRealPath(const std::string& path)
 {
-#if defined(WIN32)  && !defined(__CYGWIN__)
+#if defined(_WIN32)  && !defined(__CYGWIN__)
 
 #ifdef OSG_USE_UTF8_FILENAME
 
diff --git a/src/osgDB/FileUtils.cpp b/src/osgDB/FileUtils.cpp
index c0c8cec88..09e98f334 100644
--- a/src/osgDB/FileUtils.cpp
+++ b/src/osgDB/FileUtils.cpp
@@ -24,7 +24,7 @@ typedef char TCHAR;
 // the mac version will change soon to reflect the path scheme under osx, but
 // for now, the above include is commented out, and the below code takes precedence.
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     #include <io.h>
     #define WINBASE_DECLARE_GET_MODULE_HANDLE_EX
     #include <windows.h>
@@ -204,7 +204,7 @@ bool osgDB::makeDirectory( const std::string &path )
     {
         std::string dir = paths.top();
 
-        #if defined(WIN32)
+        #if defined(_WIN32)
             //catch drive name
             if (dir.size() == 2 && dir.c_str()[1] == ':') {
                 paths.pop();
@@ -274,7 +274,7 @@ bool osgDB::setCurrentWorkingDirectory( const std::string &newCurrentWorkingDire
 
 void osgDB::convertStringPathIntoFilePathList(const std::string& paths,FilePathList& filepath)
 {
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     char delimitor = ';';
 #else
     char delimitor = ':';
@@ -342,7 +342,7 @@ std::string osgDB::findFileInPath(const std::string& filename, const FilePathLis
         OSG_DEBUG << "itr='" <<*itr<< "'\n";
         std::string path = itr->empty() ? filename : concatPaths(*itr, filename);
 
-#ifdef WIN32
+#ifdef _WIN32
         // if combined file path exceeds MAX_PATH then ignore as it's not a legal path otherwise subsequent IO calls with this path may result in undefined behavior
         if (path.length()>MAX_PATH) continue;
 #endif
@@ -355,7 +355,7 @@ std::string osgDB::findFileInPath(const std::string& filename, const FilePathLis
             OSG_DEBUG << "FindFileInPath() : USING " << path << "\n";
             return path;
         }
-#ifndef WIN32
+#ifndef _WIN32
 // windows already case insensitive so no need to retry..
         else if (caseSensitivity==CASE_INSENSITIVE)
         {
@@ -395,7 +395,7 @@ std::string osgDB::findFileInDirectory(const std::string& fileName,const std::st
     std::string realFileName = fileName;
 
     // Skip case-insensitive recursion if on Windows
-    #ifdef WIN32
+    #ifdef _WIN32
         bool win32 = true;
     #else
         bool win32 = false;
@@ -535,7 +535,7 @@ static void appendInstallationLibraryFilePaths(osgDB::FilePathList& filepath)
 #endif
 }
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
     #include <io.h>
     #include <direct.h>
 
@@ -763,7 +763,7 @@ bool osgDB::containsCurrentWorkingDirectoryReference(const FilePathList& paths)
         convertStringPathIntoFilePathList("/usr/bin/:/usr/local/bin/",filepath);
     }
 
-#elif defined(WIN32)
+#elif defined(_WIN32)
 
     void osgDB::appendPlatformSpecificLibraryFilePaths(FilePathList& filepath)
     {
diff --git a/src/osgDB/Registry.cpp b/src/osgDB/Registry.cpp
index 2262e9dae..51f66e834 100644
--- a/src/osgDB/Registry.cpp
+++ b/src/osgDB/Registry.cpp
@@ -39,7 +39,7 @@
 
 #if defined(__sgi)
     #include <ctype.h>
-#elif defined(__GNUC__) || !defined(WIN32) || defined(__MWERKS__)
+#elif defined(__GNUC__) || !defined(_WIN32) || defined(__MWERKS__)
     #include <cctype>
     using std::tolower;
 #endif
@@ -53,7 +53,7 @@
 using namespace osg;
 using namespace osgDB;
 
-#if !defined(WIN32) || defined(__CYGWIN__)
+#if !defined(_WIN32) || defined(__CYGWIN__)
 static osg::ApplicationUsageProxy Registry_e0(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_FILE_PATH <path>[:path]..","Paths for locating datafiles");
 static osg::ApplicationUsageProxy Registry_e1(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_LIBRARY_PATH <path>[:path]..","Paths for locating libraries/ plugins");
 #else
@@ -787,7 +787,7 @@ std::string Registry::createLibraryNameForExtension(const std::string& ext)
     return prepend+"cygwin_"+"osgdb_"+lowercase_ext+OSG_LIBRARY_POSTFIX_WITH_QUOTES+".dll";
 #elif defined(__MINGW32__)
     return prepend+"mingw_"+"osgdb_"+lowercase_ext+OSG_LIBRARY_POSTFIX_WITH_QUOTES+".dll";
-#elif defined(WIN32)
+#elif defined(_WIN32)
     return prepend+"osgdb_"+lowercase_ext+OSG_LIBRARY_POSTFIX_WITH_QUOTES+".dll";
 #elif macintosh
     return prepend+"osgdb_"+lowercase_ext+OSG_LIBRARY_POSTFIX_WITH_QUOTES;
@@ -803,7 +803,7 @@ std::string Registry::createLibraryNameForNodeKit(const std::string& name)
     return "cyg"+name+OSG_LIBRARY_POSTFIX_WITH_QUOTES+".dll";
 #elif defined(__MINGW32__)
     return "lib"+name+OSG_LIBRARY_POSTFIX_WITH_QUOTES+".dll";
-#elif defined(WIN32)
+#elif defined(_WIN32)
     return name+OSG_LIBRARY_POSTFIX_WITH_QUOTES+".dll";
 #elif macintosh
     return name+OSG_LIBRARY_POSTFIX_WITH_QUOTES;
diff --git a/src/osgPlugins/OpenCASCADE/ReaderWriterOpenCASCADE.h b/src/osgPlugins/OpenCASCADE/ReaderWriterOpenCASCADE.h
index 705259820..e6a7caffa 100644
--- a/src/osgPlugins/OpenCASCADE/ReaderWriterOpenCASCADE.h
+++ b/src/osgPlugins/OpenCASCADE/ReaderWriterOpenCASCADE.h
@@ -24,7 +24,7 @@
 /// \brief header file for creating osgdb plugin for IGES format
 /// \author Abhishek Bansal, Engineer Graphics, vizExperts India Pvt. Ltd. 
 
-#ifdef WIN32
+#ifdef _WIN32
 /// \brief preproccessor macro required for compilation with open cascade
 /// \todo not sure what it does
 #define WNT
diff --git a/src/osgPlugins/cfg/Camera.cpp b/src/osgPlugins/cfg/Camera.cpp
index 10534809a..1f3fed965 100644
--- a/src/osgPlugins/cfg/Camera.cpp
+++ b/src/osgPlugins/cfg/Camera.cpp
@@ -11,7 +11,7 @@
  * OpenSceneGraph Public License for more details.
  */
 
-#ifdef WIN32
+#ifdef _WIN32
 #include <windows.h>
 #endif
 
diff --git a/src/osgPlugins/cfg/ConfigLexer.cpp b/src/osgPlugins/cfg/ConfigLexer.cpp
index 4e169efe4..a1470b7f4 100644
--- a/src/osgPlugins/cfg/ConfigLexer.cpp
+++ b/src/osgPlugins/cfg/ConfigLexer.cpp
@@ -29,7 +29,7 @@
 
 #include <stdlib.h>
 #include <iostream>
-#ifndef WIN32
+#ifndef _WIN32
 #include <unistd.h>
 #endif
 
diff --git a/src/osgPlugins/cfg/ConfigParser.cpp b/src/osgPlugins/cfg/ConfigParser.cpp
index 62d30c3f5..d42171004 100644
--- a/src/osgPlugins/cfg/ConfigParser.cpp
+++ b/src/osgPlugins/cfg/ConfigParser.cpp
@@ -210,7 +210,7 @@
 
 
 
-#ifndef WIN32
+#ifndef _WIN32
 #include <unistd.h>
 #include <sys/wait.h>
 #include <stdlib.h>
@@ -218,7 +218,7 @@
 #endif
 
 #if 0
-#ifndef WIN32
+#ifndef _WIN32
 #define SUPPORT_CPP 1
 #endif
 #endif
diff --git a/src/osgPlugins/cfg/RenderSurface.cpp b/src/osgPlugins/cfg/RenderSurface.cpp
index ffa4b9e3f..3d6da15ee 100644
--- a/src/osgPlugins/cfg/RenderSurface.cpp
+++ b/src/osgPlugins/cfg/RenderSurface.cpp
@@ -221,7 +221,7 @@ void RenderSurface::setDisplay( Display *dpy )
 
 Producer::Display *RenderSurface::getDisplay()
 {
-#ifdef WIN32
+#ifdef _WIN32
     return &_hdc;
 #else
     return _dpy;
@@ -230,7 +230,7 @@ Producer::Display *RenderSurface::getDisplay()
 
 const Producer::Display *RenderSurface::getDisplay() const
 {
-#ifdef WIN32
+#ifdef _WIN32
     return &_hdc;
 #else
     return _dpy;
@@ -434,7 +434,7 @@ void RenderSurface::setWindow( const Window win )
         return;
     }
     _win = win;
-#ifdef WIN32
+#ifdef _WIN32
     _ownWindow = false;
 #endif
 }
diff --git a/src/osgPlugins/dae/ReaderWriterDAE.cpp b/src/osgPlugins/dae/ReaderWriterDAE.cpp
index 39341977e..41e1a4056 100644
--- a/src/osgPlugins/dae/ReaderWriterDAE.cpp
+++ b/src/osgPlugins/dae/ReaderWriterDAE.cpp
@@ -26,7 +26,7 @@
 #include "daeReader.h"
 #include "daeWriter.h"
 
-#ifdef WIN32
+#ifdef _WIN32
 #include "windows.h"
 #endif
 
diff --git a/src/osgPlugins/dae/daeRMaterials.cpp b/src/osgPlugins/dae/daeRMaterials.cpp
index 5da9d608a..4763cdb5b 100644
--- a/src/osgPlugins/dae/daeRMaterials.cpp
+++ b/src/osgPlugins/dae/daeRMaterials.cpp
@@ -907,7 +907,7 @@ std::string daeReader::processImagePath(const domImage* pDomImage) const
                 OSG_WARN << "Unable to get path from URI." << std::endl;
                 return std::string();
             }
-#ifdef WIN32
+#ifdef _WIN32
             // If the path has a drive specifier or a UNC name then strip the leading /
             if (path.size() > 2 && (path[2] == ':' || (path[1] == '/' && path[2] == '/')))
                 return path.substr(1, std::string::npos);
diff --git a/src/osgPlugins/dae/daeWMaterials.cpp b/src/osgPlugins/dae/daeWMaterials.cpp
index 2be1cc665..69f207c5e 100644
--- a/src/osgPlugins/dae/daeWMaterials.cpp
+++ b/src/osgPlugins/dae/daeWMaterials.cpp
@@ -27,7 +27,7 @@
 //#include <dom/domLibrary_effects.h>
 //#include <dom/domLibrary_materials.h>
 
-#ifdef WIN32
+#ifdef _WIN32
 #include "windows.h"
 #endif
 
diff --git a/src/osgPlugins/dds/ReaderWriterDDS.cpp b/src/osgPlugins/dds/ReaderWriterDDS.cpp
index 184a3e310..26532d778 100644
--- a/src/osgPlugins/dds/ReaderWriterDDS.cpp
+++ b/src/osgPlugins/dds/ReaderWriterDDS.cpp
@@ -62,7 +62,7 @@
     #define GL_LUMINANCE4_ALPHA4    0x8043
 #endif
 
-// NOTICE ON WIN32:
+// NOTICE ON _WIN32:
 // typedef DWORD unsigned long;
 // sizeof(DWORD) = 4
 
diff --git a/src/osgPlugins/fbx/ReaderWriterFBX.cpp b/src/osgPlugins/fbx/ReaderWriterFBX.cpp
index db385c410..66c6e99d2 100644
--- a/src/osgPlugins/fbx/ReaderWriterFBX.cpp
+++ b/src/osgPlugins/fbx/ReaderWriterFBX.cpp
@@ -1,6 +1,6 @@
 #include <sstream>
 #include <memory>
-#ifndef WIN32
+#ifndef _WIN32
 #include <strings.h>//for strncasecmp
 #endif
 
@@ -339,7 +339,7 @@ ReaderWriterFBX::readNode(const std::string& filenameInit,
                 for (unsigned int i = 0; i < sizeof(authoringTools) / sizeof(authoringTools[0]); ++i)
                 {
                     if (0 ==
-#ifdef WIN32
+#ifdef _WIN32
                         _strnicmp
 #else
                         strncasecmp
diff --git a/src/osgPlugins/md2/ReaderWriterMD2.cpp b/src/osgPlugins/md2/ReaderWriterMD2.cpp
index d5c918d40..1c1bd3ffc 100644
--- a/src/osgPlugins/md2/ReaderWriterMD2.cpp
+++ b/src/osgPlugins/md2/ReaderWriterMD2.cpp
@@ -29,7 +29,7 @@
 #include <string.h>
 #include <fcntl.h>
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
 #  include <io.h>
 #else
 #  include <unistd.h>
diff --git a/src/osgPlugins/osc/osc/OscHostEndianness.h b/src/osgPlugins/osc/osc/OscHostEndianness.h
index fe135f46b..839bc26f9 100644
--- a/src/osgPlugins/osc/osc/OscHostEndianness.h
+++ b/src/osgPlugins/osc/osc/OscHostEndianness.h
@@ -42,7 +42,7 @@
 // you can define one of the above symbols from the command line
 // then you don't have to edit this file.
 
-#elif defined(__WIN32__) || defined(WIN32) || defined(WINCE)
+#elif defined(__WIN32__) || defined(_WIN32) || defined(WINCE)
 
 // assume that __WIN32__ is only defined on little endian systems
 
diff --git a/src/osgPlugins/osc/osc/OscOutboundPacketStream.cpp b/src/osgPlugins/osc/osc/OscOutboundPacketStream.cpp
index c7ba9da82..3f495028d 100644
--- a/src/osgPlugins/osc/osc/OscOutboundPacketStream.cpp
+++ b/src/osgPlugins/osc/osc/OscOutboundPacketStream.cpp
@@ -33,7 +33,7 @@
 #include <stdlib.h>
 #include <assert.h>
 
-#if defined(__WIN32__) || defined(WIN32)
+#if defined(__WIN32__) || defined(_WIN32)
 #include <malloc.h> // for alloca
 #endif
 
diff --git a/src/osgPlugins/osc/osc/OscTypes.h b/src/osgPlugins/osc/osc/OscTypes.h
index b31911143..ead9d758b 100644
--- a/src/osgPlugins/osc/osc/OscTypes.h
+++ b/src/osgPlugins/osc/osc/OscTypes.h
@@ -35,7 +35,7 @@ namespace osc{
 
 // basic types
 
-#if defined(__BORLANDC__) || defined(_MSC_VER)
+#if defined(__BORLANDC__) || (defined(_MSC_VER) && !defined(__clang__))
 
 typedef __int64 int64;
 typedef unsigned __int64 uint64;
diff --git a/src/osgPlugins/pdf/ReaderWriterPDF.cpp b/src/osgPlugins/pdf/ReaderWriterPDF.cpp
index ed664eb73..23a04404e 100644
--- a/src/osgPlugins/pdf/ReaderWriterPDF.cpp
+++ b/src/osgPlugins/pdf/ReaderWriterPDF.cpp
@@ -121,7 +121,7 @@ class PopplerPdfImage : public osgWidget::PdfImage
             foundFile = osgDB::getRealPath(foundFile);
             OSG_NOTICE<<"foundFile = "<<foundFile<<std::endl;
 
-#if defined(WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__)
             std::string uri = std::string("file:///") + foundFile;
 #else
             std::string uri = std::string("file:") + foundFile;
diff --git a/src/osgPlugins/ply/plyfile.cpp b/src/osgPlugins/ply/plyfile.cpp
index e75da1c5f..228d0360a 100644
--- a/src/osgPlugins/ply/plyfile.cpp
+++ b/src/osgPlugins/ply/plyfile.cpp
@@ -55,7 +55,7 @@ WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
     #pragma warning( disable : 4996 )
 #endif
 
-#ifdef WIN32
+#ifdef _WIN32
 #    ifndef LITTLE_ENDIAN
 #    define LITTLE_ENDIAN
 #    endif
diff --git a/src/osgPlugins/shp/ESRIShape.h b/src/osgPlugins/shp/ESRIShape.h
index 1f1467429..afa13f970 100644
--- a/src/osgPlugins/shp/ESRIShape.h
+++ b/src/osgPlugins/shp/ESRIShape.h
@@ -2,7 +2,7 @@
 #define OSG_SHAPE_H
 
 #include <stdio.h>
-#ifndef WIN32
+#ifndef _WIN32
 #include <unistd.h>
 #endif
 #include <osg/Referenced>
diff --git a/src/osgPlugins/shp/ESRIShapeParser.cpp b/src/osgPlugins/shp/ESRIShapeParser.cpp
index 4245f2232..d92a1eebb 100644
--- a/src/osgPlugins/shp/ESRIShapeParser.cpp
+++ b/src/osgPlugins/shp/ESRIShapeParser.cpp
@@ -20,7 +20,7 @@ ESRIShapeParser::ESRIShapeParser(const std::string fileName, bool useDouble, boo
     int fd = 0;
     if( !fileName.empty() )
     {
-#ifdef WIN32
+#ifdef _WIN32
         if( (fd = open( fileName.c_str(), O_RDONLY | O_BINARY )) < 0 )
 #else
         if( (fd = open( fileName.c_str(), O_RDONLY )) < 0 )
diff --git a/src/osgPlugins/shp/XBaseParser.cpp b/src/osgPlugins/shp/XBaseParser.cpp
index 61119ec9e..d1eb0fc22 100644
--- a/src/osgPlugins/shp/XBaseParser.cpp
+++ b/src/osgPlugins/shp/XBaseParser.cpp
@@ -87,7 +87,7 @@ XBaseParser::XBaseParser(const std::string& fileName):
     if (!fileName.empty())
     {
         int fd = 0;
-#ifdef WIN32
+#ifdef _WIN32
         if( (fd = open( fileName.c_str(), O_RDONLY | O_BINARY )) < 0 )
 #else
         if( (fd = ::open( fileName.c_str(), O_RDONLY )) < 0 )
diff --git a/src/osgText/Font.cpp b/src/osgText/Font.cpp
index b9d413f20..f56122feb 100644
--- a/src/osgText/Font.cpp
+++ b/src/osgText/Font.cpp
@@ -102,7 +102,7 @@ std::string osgText::findFontFile(const std::string& str)
     if (!initialized)
     {
         initialized = true;
-    #if defined(WIN32)
+    #if defined(_WIN32)
         osgDB::convertStringPathIntoFilePathList(
             ".;C:/winnt/fonts;C:/windows/fonts",
             s_FontFilePath);
diff --git a/src/osgViewer/GraphicsWindowWin32.cpp b/src/osgViewer/GraphicsWindowWin32.cpp
index 88156a66c..e895f98f7 100644
--- a/src/osgViewer/GraphicsWindowWin32.cpp
+++ b/src/osgViewer/GraphicsWindowWin32.cpp
@@ -1101,7 +1101,7 @@ bool Win32WindowingSystem::changeScreenSettings( const osg::GraphicsContext::Scr
     // Start by testing if the change would be successful (without applying it)
     //
 
-    unsigned int result = ::ChangeDisplaySettingsEx(displayDevice.DeviceName, &deviceMode, NULL, CDS_TEST, NULL);
+    int result = ::ChangeDisplaySettingsEx(displayDevice.DeviceName, &deviceMode, NULL, CDS_TEST, NULL);
     if (result==DISP_CHANGE_SUCCESSFUL)
     {
         result = ::ChangeDisplaySettingsEx(displayDevice.DeviceName, &deviceMode, NULL, 0, NULL);
diff --git a/src/osgWidget/Input.cpp b/src/osgWidget/Input.cpp
index 3b565b04a..899d7fd97 100644
--- a/src/osgWidget/Input.cpp
+++ b/src/osgWidget/Input.cpp
@@ -5,7 +5,7 @@
 #include <osgWidget/Input>
 #include <iterator>
 
-#ifdef WIN32
+#ifdef _WIN32
 #include <windows.h>
 #endif
 
@@ -512,7 +512,7 @@ bool Input::keyDown(int key, int mask, const WindowManager*)
         {
             std::string data;
 // Data from clipboard
-#ifdef WIN32
+#ifdef _WIN32
             if (::OpenClipboard(NULL))
             {
                 HANDLE hData = ::GetClipboardData( CF_TEXT );
@@ -571,7 +571,7 @@ bool Input::keyDown(int key, int mask, const WindowManager*)
                 data = selection.createUTF8EncodedString();
 
 // Data to clipboard
-#ifdef WIN32
+#ifdef _WIN32
                 if(::OpenClipboard(NULL))
                 {
                     ::EmptyClipboard();