Hello Piyush Bhatt,
Perhaps the report viewer project references the correct assemblies which allow the report to retrieve its data. The unit test project, on the other hand, might not reference the required assemblies and the data cannot be retrieved there.
Since you do not need to create any unit tests for Telerik Reporting modules, you can only retrieve the data and check that it is correct in your unit test project i.e., test only the GetData() method. Testing that Telerik Reporting produces correct report output based on given input data is done on our end.
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