The RuntimeKey property specifies a runtime key to be used for the component. The value for the RuntimeKey property is provided by Exontrol, by the time you purchased the component. The RuntimeKey value is not the same as your development license key. Without a runtime key there are limitations of using the control. For instance, the RecurAll method gets only 16 occurrences, if using the evaluation version or the RuntimeKey property is not specifying a valid, not expired runtime-key.