diff --git a/libsrc/occ/vsocc.cpp b/libsrc/occ/vsocc.cpp
index d4631da7..d76395c1 100644
--- a/libsrc/occ/vsocc.cpp
+++ b/libsrc/occ/vsocc.cpp
@@ -2,6 +2,23 @@
 
 #ifdef OCCGEOMETRY
 
+
+/*** Windows headers ***/
+#ifdef _MSC_VER
+# define WIN32_LEAN_AND_MEAN
+# ifndef NO_PARALLEL_THREADS
+#  ifdef MSVC_EXPRESS
+#  else
+#   include <afxwin.h>
+#   include <afxmt.h>
+#  endif // MSVC_EXPRESS
+# endif
+# include <windows.h>
+# undef WIN32_LEAN_AND_MEAN
+# include <winnt.h>
+#else // Not using MC VC++
+#endif
+
 #include <mystdlib.h>
 #include <myadt.hpp>
 #include <meshing.hpp>