You may receive an ASP.NET or SharePoint application error when trying to run a report that takes a while in SharePoint Integrated mode. It seems that the standard timeout is well over 2 hours in SQL Native mode, but in SharePoint integrated mode, the default timeout is reduced to 2 minutes.
To extend the SQL Reporting Services timeout, you’ll need to modify the web.config of the SharePoint site that is hosting your reports.
- Browse for the node <httpRuntime> within the web.config
- Add the property executionTimeout=”9000″ before the end tag
- Save and close the file


