diff --git a/src/errors.h b/src/errors.h
index 0099431..dd2bc95 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3185,7 +3185,7 @@
 EXTERN char e_no_white_space_allowed_before_separator_str[]
 	INIT(= N_("E1242: No white space allowed before separator: %s"));
 #endif
-#ifdef FEAT_GUI_GTK
+#if defined(FEAT_GUI_GTK) || defined(FEAT_GUI_MSWIN)
 EXTERN char e_ascii_code_not_in_range[]
 	INIT(= N_("E1243: ASCII code not in 32-127 range"));
 #endif