Take a look at the following online demo of RadScheduler: http://demos.telerik.com/aspnet-ajax/scheduler/examples/outlook2007/defaultcs.aspx
. It shows how to filter appointments by resources by checking/unchecking the CheckBoxes representing the appointments' resources.
In you case if you are using a RadTreeView to represent the appointments' resources you should take advantage of the client API
of the RadTreeView to manipulate the appointments shown in the RadScheduler.
the Telerik team
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