I have created the custom data source Provider. I have edited the config file RSReportDesigner.config and RSPreviewPolicy.config. I am able to see my custom data source provider in data source list while creating the data source in SSRS (Visual Studio). While creating dataset, iam able to execute query and get data.
But, when i try to preview the report it display following error: An attempt has been made to use Data Extension 'CUSTOM_DATASOURCE' that is either not registered for this report server or is not supported in this edition of Reporting Services