Recently I was configuring SSRS to run in Integrated mode with SharePoint 2010. All the pieces seems to be installed correctly and when trying to configure Reporting Services Integration under Central Admin –> General Settings –> Reporting Services Integration but kept getting the following error.

System.Web.Services.Protocols.SoapException: The permissions granted to user 'Domain\User"’ are insufficient for performing this operation. ---> Microsoft.ReportingServices.Diagnostics.Utilities.AccessDeniedException: The permissions granted to user 'Domain\User' are insufficient for performing this operation. at Microsoft.ReportingServices.WebServer.ReportingService2010Impl.GetReportServerConfigInfo(Boolean scaleOut, String& ServerConfigInfo) at Microsoft.ReportingServices.WebServer.ReportingService2010.GetReportServerConfigInfo(Boolean ScaleOut, String& ServerConfigInfo)   

Not sure why this was happening; Confirmed that “Domain\User” has dbo permissions on reportserverDB and tempDBs. Confirmed that Central Administration pool account also has permission to the reporting services. After few hours of brain churning, I decided to add the “Domain\User” as local administrator and voila. Everything started working. But I still wasn’t convinced why I had to do that. So, I started my expedition via bing. And voila, I found the Microsoft article that references this.

http://msdn.microsoft.com/en-us/library/bb326213.aspx

Refer to line # 6.

So, just to sum up, the resolution is to add the user account (service account) running the reporting service as Local Administrator on the box where reporting services is installed and configured. This could be a dedicated machine in the farm or installed on one of the application server.