Hello Eric,
When you disable the embedded skin for RadDatePicker for ASP.NET AJAX, you need to register manually the skins/images used by the control in order to display them as expected. Review the following online help articles for more details:
http://www.telerik.com/help/aspnet-ajax/disabling_embedded_resources.html
http://www.telerik.com/help/aspnet-ajax/calendar_appearanceskins.html (paragraph customizing skins)
In case you merely want to disable or hide the popup button, set the
DatePopupButton -> Visible/Enabled property of the date picker to
False or replace the picker with
RadDateInput instead.
Kind regards,
Stephen
the Telerik team
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