Telerik Reporting viewers and the reporting ReportProcessor work only with Telerik Reports.
Due to the general mismatch in both products - Telerik Reporting and SSRS - reports, there are currently no converters to ease the migration. Our recommendation is to check the following articles elaborating on our reports structure and data binding. Then you will have to recreate your existing reports.
Perhaps the Standalone Report Designer would be the easiest approach if you decide to write your own converters. The tools is a desktop program allowing you to create Telerik reports in XML format, without using Visual Studio.
Let us know if you have any further questions.
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