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May 26, 2011 06:40 by
Scott
Recently someone asked me to check a Reporting Services report that always resulted in an Unexpected Error. The report server was configured for Sharepoint Integrated Mode
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You need to notice Execution timeout of SharePoint. You can change this timeout setting in the web.config of your Sharepoint site, by default in c\:inetpub\wwwroot\wss\VirtualDirectories\80.
In this web.config you will find an XML node called “httpRuntime”. In this node you have to add an extra tag: executionTimeout=”9000″:
<httpRuntime maxRequestLength=”51200″ executionTimeout=”9000″ />
Save and close the file and do an IISReset. When you run the report again, you won’t get this error anymore.
I also checked the web.config of the Report Manager, but in Native Mode this seems to be the default:
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Good luck