This utility scans the Users catalog for inconsistencies. It checks whether all catalogs, sets and templates that are assigned to users/roles are available. If an item is found that is assigned but not available, it is recognized as invalid and you will be asked whether the according assignments should be deleted. You can have Cumulus do this item for item or just ask you once for all items. Be careful when deleting assignments for catalogs: Cumulus considers catalogs as available only if they are opened with the Cumulus Server.