Which KendoUI version do you use? If it is under 2015.1.429 please at first upgrade because the latest service pack release contains a lot of bug fixes related to the virtualization feature.
In case the upgrade does not resolve the problem I kindly ask you to create an isolated example (Kendo Dojo
) which I can run and examine locally. This will give me the opportunity to explore in details the server response, DropDownList/DataSource configuration and assist you further.
Thank you in advance for the cooperation.
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