The Report Server supports CsvDataSource and SqlDataSource components. The usage of an ObjectDataSource will require manual settings in the Report Server and Scheduler configuration files similar to these of the Standalone Report Designer. For more details, please check Extending Report Designer
and Previewing a report definition that uses an external assembly
Note that changes in running web applications lead to restart in IIS.
Please feel free to add a feature request for having support for external assemblies in Telerik Report Server - feedback portal
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