Question: How do you solve this error in Asp.Net 6 Runtime Binder Exception. This error seems to only happen on runtime. The Error states "RuntimeBinderException: 'System.Dynamic.DynamicObject'does not contain a definition for 'Modal'". Answer: This error is due to a null object, make sure that the Object you are binding to the ViewBag.MyObect = MyOBJ is not empty. Check for null exception before you do your binding.