diff --git a/html/cgi-bin/firewall.cgi b/html/cgi-bin/firewall.cgi
index 8b02b0446..b313d4bb2 100755
--- a/html/cgi-bin/firewall.cgi
+++ b/html/cgi-bin/firewall.cgi
@@ -659,6 +659,8 @@ sub checktarget
 							if (&General::validport($_)){
 								push (@values,$_);
 							}else{
+								$errormessage=$Lang::tr{'fwdfw err tgt_port'};
+								return $errormessage;
 							}
 						}
 					}