Cannot add vlan rows if locked

EduNetworkBuilder/VLANConfig.cs

@@ -59,6 +59,8 @@ namespace EduNetworkBuilder
                 {
                     dgv_VLANNames.Columns[2].ReadOnly = LockedNames;
                 }
+                if (LockedNames)
+                    dgv_VLANNames.AllowUserToAddRows = false;
             }
         }