When RadScheduler is bound to a web service, post-back to the server is not made when the AdvancedForm is opened or closed.
More information about the web service binding of RadScheduler could be found at the following help article at our website: RadScheduler: Web Service Binding
For the customization of the AdvancedForm of the RadScheduler, you could refer to the following link:
Customization of the AdvancedForm: Using Advanced Templates
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