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



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:



Good luck