diff --git a/src/gui_w32.c b/src/gui_w32.c
index 128869e..e4d2570 100644
--- a/src/gui_w32.c
+++ b/src/gui_w32.c
@@ -1574,6 +1574,10 @@
 #endif
 
 #ifdef FEAT_EVAL
+# if _MSC_VER < 1400
+/* HandleToLong() only exists in compilers that can do 64 bit builds */
+#  define HandleToLong(h) ((long)(h))
+# endif
     /* set the v:windowid variable */
     set_vim_var_nr(VV_WINDOWID, HandleToLong(s_hwnd));
 #endif