Hello mary kay,
When using shared calendars and AJAX, you need to make sure the shared calendar is loaded onto the page on initial load. The shared calendar cannot be loaded when you make an AJAX callback. If your shared calendar is not initially loaded on page, it client object will not be properly initialized and you will get exceptions stating some object does not support a property or a method.
Alternatively, you need to make sure your shared calendar is placed inside your AJAX-ified content, so that whenever you make an AJAX callback, your shared calendar container is also updated.
the Telerik team