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https://blog.devoworx.net/2014/04/21/the-base-class-includes-the-field-xxx-but-its-type-microsoft-reporting-webforms-reportviewer-is-not-compatible-with-the-type-of-control-microsoft-reporting-webforms-reportviewer/
The base class includes the field 'XXX', but its type is not compatible with the type of control "Microsoft.Reporting.WebForms.ReportViewer"