"Loading..." text in Combobox with Virtual Scrolling is visible on first set of items loading. It shows first time "Loading..." text. on scrolling it loads items from PageMethods/WebService but "Loading..." text it not visible i.e. because it is first <LI> item so it is not visible. Instead of first <LI> item, it should be at position where it always display while loading more items. same issue is also in telerik demo website : http://demos.telerik.com/aspnet-ajax/combobox/examples/populatingwithdata/autocompletesql/defaultcs.aspx