I don't want to use RadScheduler1_AppointmentCreated because it is not about existing appointment records. I have an SQL table that dictates, for a given resource, what days of the week and hours of a given day our users are allowed to create appointments. I want to be able to disable a cell with code-behind. The change of backcolor for a give cell will give our users a visual representation of the resource's availability. Thanks in advance for your help.