diff --git a/Scripts/AutoBuild_Function.sh b/Scripts/AutoBuild_Function.sh
index c7eb16e..164ef2b 100755
--- a/Scripts/AutoBuild_Function.sh
+++ b/Scripts/AutoBuild_Function.sh
@@ -145,7 +145,7 @@ sed -i 's/services/vpn/g' /usr/lib/lua/luci/view/v2ray_server/users_list_status.
 sed -i 's/services/vpn/g' /usr/lib/lua/luci/view/v2ray_server/users_list_status.htm
 sed -i 's/services/vpn/g' /usr/lib/lua/luci/view/v2ray_server/v2ray.htm
 
-if [ -z "$(grep "REDIRECT --to-ports 53" /etc/firewall.user)" ]
+if [ -z "\$(grep "REDIRECT --to-ports 53" /etc/firewall.user 2> /dev/null)" ]
 then
 	echo '#iptables -t nat -A PREROUTING -p udp --dport 53 -j REDIRECT --to-ports 53' >> /etc/firewall.user
 	echo '#iptables -t nat -A PREROUTING -p tcp --dport 53 -j REDIRECT --to-ports 53' >> /etc/firewall.user
@@ -468,4 +468,4 @@ Copy() {
 		cp -a $1 $2/$3
 	fi
 	[[ $? == 0 ]] && ECHO "Done." || ECHO "Failed."
-}
\ No newline at end of file
+}