Running large reports can take a long time to complete. When you preview large reports from PM Compass (Reports » <report category> » <report> » Preview), the connection to the server may time out before the report is completed. If you get a time out error, Deltek recommends scheduling the report to run on the Process Server, which creates an archive of the report that you can view in your dashboard when complete. You can do this by clicking Schedule on the Reporting toolbar which displays the Schedule dialog box.
When you schedule the report, you can select Send Process Status Email Alert to Submitter to receive an email when the report finishes or fails. When the report is completed, you can view it by clicking on the Archived Reports tab (Reports » <report category>). If it fails (it is not on the Archive tab), you can check the Report Logging tab (Administration » Report Administration) to find the report. It displays rsInternalError in the Status column if it has failed.
If you encounter any errors when running reports and you want to troubleshoot them, you can find additional details in the SQL Server Reporting Services log files on the Report Server. Your Administrator can review these logs. Microsoft provides details on what is stored in the logs, where to find them, and how to configure them. See this link for more information: Report Server Service Trace Log.
Load Reports using Report Administration