This error occurs when the Syncfusion assemblies are not referred in the web application.
To resolve the issue, refer to the corresponding assemblies for adding Syncfusion ASP.NET controls in the web applications as given in the following link,
In order to render the controls, you have to add the required script files and CSS files in your application. You can follow the steps given in the UG documentation link as follows:
|Article ID:||Published Date:||Last Revised Date:||Platform:||Control:|
|3890||02/12/2015||02/12/2015||ASP.NET Web Forms||General|