diff --git a/Source/cmFileCommand.cxx b/Source/cmFileCommand.cxx
index 91cecb359f..dc97e37e36 100644
--- a/Source/cmFileCommand.cxx
+++ b/Source/cmFileCommand.cxx
@@ -42,6 +42,10 @@
 #include "cmFileLockResult.h"
 #endif
 
+#if defined(_WIN32)
+#include <windows.h>
+#endif
+
 class cmSystemToolsFileTime;
 
 // Table of permissions flags.