diff --git a/src/map/clif.h b/src/map/clif.h
index 23afc87999..e2f5da66eb 100644
--- a/src/map/clif.h
+++ b/src/map/clif.h
@@ -34,6 +34,7 @@ enum e_party_member_withdraw;
 struct sale_item_data;
 enum mail_inbox_type;
 struct mail_message;
+enum mail_attachment_type;
 #include <stdarg.h>
 
 enum { // packet DB