The Server Groups Analysis reports on server groups that are defined in the landscape along with any reports configured to process on those server groups. Additionally, this analysis reports on any documents that are configured to process on an "orphaned server group".
Each server group in the landscape is represented as a tab. Click on the tab to see information about that server group, the member servers of that group, and the reports configured to use that server group.
The Orphaned Reports tab shows any reports that are configured to use a server group that has been deleted. In this situation, the report cannot be processed because there are no servers available to support the view/schedule request.