diff --git a/include/objbase.h b/include/objbase.h
index 4c46c276537..747fd75c838 100644
--- a/include/objbase.h
+++ b/include/objbase.h
@@ -3,7 +3,7 @@
 
 #define _OBJBASE_H_
 
-#include "wine/obj_base.h"
+#include "unknwn.h"
 
 /* the following depend only on obj_base.h */
 #include "wine/obj_misc.h"
diff --git a/include/unknwn.h b/include/unknwn.h
index 1803cb2b9d0..c9a26aeddc4 100644
--- a/include/unknwn.h
+++ b/include/unknwn.h
@@ -1,8 +1,14 @@
 #ifndef __WINE_UNKNWN_H
 #define __WINE_UNKNWN_H
 
+#include "rpc.h"
+#include "rpcndr.h"
 
 #include "wine/obj_base.h"
 
+#ifndef COM_NO_WINDOWS_H
+#include "windows.h"
+#include "ole2.h"
+#endif
 
 #endif /* __WINE_UNKNWN_H */