SSRS also requires that eB credentials be configured.

1. Go to Start > All Programs > Microsoft SQL Server 2012 > Configuration Tools > Reporting Services Configuration Manager. The Reporting Services Configuration Connection and Reporting Services Configuration Manager dialogs open.
2. In the Reporting Services Configuration Connection dialog, type the Server Name (if not already displayed) and from the Report Server Instance drop-down, select the report server. Click Connect.
3. In Reporting Services Configuration Manager dialog Connect pane, click Report Manager URL. Two URLs display.
4. Click the second URL The SQL Server Reporting Services Home page opens in your browser.
5. On the home page, click the datasource you are using and then in the next window, select the datasource again.
6. In the datasource window, from the Connect using options, select Credentials supplied by the user running the report.