diff --git a/neo/renderer/qgl.h b/neo/renderer/qgl.h
index ef0e6ece..d2487884 100644
--- a/neo/renderer/qgl.h
+++ b/neo/renderer/qgl.h
@@ -34,7 +34,7 @@ If you have questions concerning this license or the applicable additional terms
 
 #if defined( _WIN32 )
 
-#include <gl/gl.h>
+#include <GL/gl.h>
 
 #elif defined( MACOS_X )
 
diff --git a/neo/sys/win32/win_main.cpp b/neo/sys/win32/win_main.cpp
index 2d283d1d..6e7d7b72 100644
--- a/neo/sys/win32/win_main.cpp
+++ b/neo/sys/win32/win_main.cpp
@@ -36,7 +36,7 @@ If you have questions concerning this license or the applicable additional terms
 #include <io.h>
 #include <conio.h>
 #include <mapi.h>
-#include <ShellAPI.h>
+#include <shellapi.h>
 
 #ifndef __MRC__
 #include <sys/types.h>
diff --git a/neo/sys/win32/win_shared.cpp b/neo/sys/win32/win_shared.cpp
index 7efc1181..8b760861 100644
--- a/neo/sys/win32/win_shared.cpp
+++ b/neo/sys/win32/win_shared.cpp
@@ -42,7 +42,7 @@ If you have questions concerning this license or the applicable additional terms
 #ifndef	ID_DEDICATED
 #include <comdef.h>
 #include <comutil.h>
-#include <Wbemidl.h>
+#include <wbemidl.h>
 
 #pragma comment (lib, "wbemuuid.lib")
 #endif
diff --git a/neo/sys/win32/win_snd.cpp b/neo/sys/win32/win_snd.cpp
index ae48ab11..b3a966de 100644
--- a/neo/sys/win32/win_snd.cpp
+++ b/neo/sys/win32/win_snd.cpp
@@ -29,7 +29,7 @@ If you have questions concerning this license or the applicable additional terms
 #pragma hdrstop
 
 // DirectX SDK
-#include <DxErr.h>
+#include <dxerr8.h>
 
 #include <ks.h>
 #include <ksmedia.h>