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Staring from version 4.2 Web Workbench now has a Report Server Local Mode that removes the need for SSRS to render web reports. With this mode turned on, the web application renders the reports locally with Microsoft ReportViewer Controls.
Web Workbench requires uses SSRS to render reports in the web browser. In most cases SSRS is installed on the same host as the SQL Server, although it may also be installed on a separate server if using non-Express versions of SQL Server.
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