--- a/dom/media/platforms/wmf/DXVA2Manager.h
+++ b/dom/media/platforms/wmf/DXVA2Manager.h
@@ -6,17 +6,17 @@
 #if !defined(DXVA2Manager_h_)
 #define DXVA2Manager_h_
 
 #include "MediaInfo.h"
 #include "WMF.h"
 #include "mozilla/Mutex.h"
 #include "nsAutoPtr.h"
 #include "nsRect.h"
-#include "D3D11.h"
+#include "d3d11.h"
 
 namespace mozilla {
 
 namespace layers {
 class Image;
 class ImageContainer;
 class KnowsCompositor;
 }