We have installed the web adaptor and configured some of our map services to be available only to certain groups, based on a user's windows login info. Everything is working fine in our Silverlight map, users are not able to turn on or do any queries on the restricted layers. However I would like to have a dialog box pop up when the user tries to turn on a restricted layer, to tell them that they do not have permission to view this layer and if they think they should they need to speak to so and so. I'm just not sure where in my code to test whether the user has permission in order to pop up a dialog box. Currently when a restricted user turns the layer on, nothing happens - the checkbox appears checked but the geometry just does not show up. I know this might be vague so please let me know if I should post any code to clarify.