diff --git a/src/ThreadVisualisation.cpp b/src/ThreadVisualisation.cpp
index b3bfdfbd9e12033061a3b349fd03888c53db8e0b..00c437c1d9f3517894ed9dddd0adb19c2b9deeba 100644
--- a/src/ThreadVisualisation.cpp
+++ b/src/ThreadVisualisation.cpp
@@ -264,7 +264,7 @@ void ThreadVisualisation::run()
 
     //CAUTION: this is necessary for WIN32 to update the window name
     // but his will freeze your system on linux
-#ifdef WIN32
+#ifdef _WIN32
     renderWindow->Render();
 #endif
 
diff --git a/src/TimerCallback.cpp b/src/TimerCallback.cpp
index 6175b8649837c5407915e285ae1d79791573aaa5..803d5f39a6b187dd3cfec82c26db622d6f17f0ab 100644
--- a/src/TimerCallback.cpp
+++ b/src/TimerCallback.cpp
@@ -39,7 +39,7 @@
 #include <iostream>
 
 
-#ifdef WIN32
+#ifdef _WIN32
 #include <vtkAVIWriter.h>
 #include <windows.h>
 #define TRAVISTO_FFMPEG
@@ -250,7 +250,7 @@ void TimerCallback::Execute(vtkObject *caller, unsigned long eventId,
                     extern_launch_recording=false; //reset
 
                     windowToImageFilter=vtkWindowToImageFilter::New();
-#ifdef WIN32
+#ifdef _WIN32
                     pAVIWriter=vtkAVIWriter::New();
 #endif