When you open a report on a Microsoft SharePoint site, you get the following message:
The report cannot be displayed. This report requires an HTTP handler entry in the HTTP handlers section in the web application web.config.
Microsoft Dynamics NAV Portal Framework uses Microsoft Report Viewer 2010 for displaying reports. This requires that the ASP.NET web handler file for Microsoft Report Viewer is configured in the web.config file of the SharePoint application for the site.
To configure the Microsoft Report Viewer in the web.config
For more information, see How to: Configure Microsoft Report Viewer for the Microsoft Dynamics NAV Web Client and SharePoint Client.