diff --git a/usr/local/www/interfaces_assign.php b/usr/local/www/interfaces_assign.php
index 2e368e4af1..33032ec862 100755
--- a/usr/local/www/interfaces_assign.php
+++ b/usr/local/www/interfaces_assign.php
@@ -262,20 +262,23 @@ if ($_GET['act'] == "del") {
         			services_dhcpd_configure();
 		}
 
-		if ($config['filter']['rule'] > 0)
-       	 	foreach ($config['filter']['rule'] as $x => $rule) {
+		if ($config['filter']['rule'] > 0) {
+       	 		foreach ($config['filter']['rule'] as $x => $rule) {
                 	        if($rule['interface'] == $id)
                		                 unset($config['filter']['rule'][$x]);
+			}
         	}
-		if ($config['nat']['advancedoutbound']['rule'] > 0)
-        	foreach ($config['nat']['advancedoutbound']['rule'] as $x => $rule) {
+		if (is_array($config['nat']['advancedoutbound']) && $config['nat']['advancedoutbound']['rule'] > 0) {
+        		foreach ($config['nat']['advancedoutbound']['rule'] as $x => $rule) {
                 	        if($rule['interface'] == $id)
            	    	                 unset($config['nat']['advancedoutbound']['rule'][$x]['interface']);
-        	}
-        	if (count($config['nat']['rule']) > 0) 
-        	foreach ($config['nat']['rule'] as $x => $rule) {
+        		}
+		}
+        	if (count(is_array($config['nat']['rule']) && $config['nat']['rule']) > 0) {
+        		foreach ($config['nat']['rule'] as $x => $rule) {
                         	if($rule['interface'] == $id)
                 	                unset($config['nat']['rule'][$x]['interface']);
+			}
         	}
 
 		write_config();