I have a BI site configured with Excel and Reporting services and all the other required services. I have extended this site and all is fine when I use farm account accessing the site through Internet.
When I use a account with a SharePoint Group 'Read' permission, I can use PowerView for SharePoint reports and SSRS report (a parametrised report deployed to document library) but I get following error for Excel PivotChart report:
'Can't Contact the Server. We're not able able to contact the server. It might not be responding, or your internet connection may have been interrupted. Please try again.'
The Excel PivotChart report renders fine but is not able to refresh data when slicers applied hence the error.
I have spend a lot of time to resolve the error but I am unable to find out why if a SSRS report can refresh data, a Excel PivotChart can not using the same account. I can not find relevant message in ULS and Event Viewer just registers:
'Microsoft.AnalysisServices.SPAddin.UsageProcessingTimerJob threw an exception. More information is included below. Call to Excel Services returned an error.'
Please help me to resolve the error.