I am trying to upgrade all of our RDLs to Reporting Services 2008. The reports execute just fine in Report Manager and Report Server from the box itself. The reports we have setup to load as a PDF also work fine. However, the reports we have setup to load in the Report Viewer will not execute. I know they are not executing at all because no entry is being made to the ExecutionLog table. I've tried upgrading the Report Viewer assemblies to the 2008 versions but that didn't help. Does anyone have any other ideas for me? Thank you very much for your help.