diff --git a/EduNetworkBuilder/NetworkDevice.cs b/EduNetworkBuilder/NetworkDevice.cs
index c57ff56..8888403 100644
--- a/EduNetworkBuilder/NetworkDevice.cs
+++ b/EduNetworkBuilder/NetworkDevice.cs
@@ -3375,6 +3375,7 @@ namespace EduNetworkBuilder
 
         public bool FirewallAllows(string inIF, string outIF)
         {
+            if (!HasAdvFirewall) return true;
             foreach(FirewallRule fwr in FirewallRules)
             {
                 if(fwr.Source == inIF && fwr.Destination == outIF)