I tried to set a focused date for the calendar on button click and it is working fine.
sender, EventArgs e)
RadCalendar2.FocusedDate = DateTime.Now.AddDays(123);
Could you confirm that you set a valid date to focus?
the Telerik team
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed