diff --git a/src/proto.h b/src/proto.h
index 1f68b21..a7b7838 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -38,17 +38,9 @@
 # if defined(UNIX) || defined(__EMX__) || defined(VMS)
 #  include "os_unix.pro"
 # endif
-# if defined(MSDOS) || defined(WIN16)
+# if defined(MSDOS)
 #  include "os_msdos.pro"
 # endif
-# ifdef WIN16
-   typedef LPSTR LPWSTR;
-   typedef LPCSTR LPCWSTR;
-   typedef int LPBOOL;
-#  include "os_win16.pro"
-#  include "os_mswin.pro"
-#  include "winclip.pro"
-# endif
 # ifdef WIN3264
 #  include "os_win32.pro"
 #  include "os_mswin.pro"