I have a problem related to the SharePoint SSRS service after the SQL server upgrading.
We have SP farm based on SharePoint 2013 SP1 (Service Pack 1 for Microsoft SharePoint Server 2013 (KB2880552) 64-Bit Edition 15.0.4571.1502) and SQL server 2012 SP1 (11.0.5058).
Mainly we are using BI services(Excel, SSRS in SharePoint mode, PowerPivot). System version on database server is 2008R2. We got the same error on different environments doesn't matter how many servers are in the farm and which services are enabled.
Everything works just fine, but when we are upgrading SQL server from SP1 to any higher version we started receives the following error message when we try to perform any operation with RDL reports.
"The permissions granted to user 'i:0#.f|ldapmembership|dmotest' are insufficient for performing this operation. ---> Microsoft.ReportingServices.Diagnostics.Utilities.AccessDeniedException: The permissions granted to user 'i:0#.f|ldapmembership|dmotest' are insufficient for performing this operation."
Our SSRS service is running under a specific service account which has all rights. I would like to know how we can proceed with this error or is there any CU which we can install to overcome this issue.
Any help would be appreciated!