Content databases contain orphaned Apps (SharePoint Server)
APPLIES TO: 
2013 2016 2019 Subscription Edition 
SharePoint in Microsoft 365
Rule Name: Content databases contain orphaned Apps.
Summary: In some situations, a content database that is used by SharePoint Server may become corrupted. The corrupted database may contain orphaned apps. Orphaned apps are not accessible, which causes unnecessary resource and license consumption and may result in failures in SharePoint upgrade.
Cause: There are orphaned apps in the content databases.
Resolution: Remove the orphaned apps.
- The content database has orphaned apps on a site collection. Remove these apps. For more information, see Remove app for SharePoint instances from a SharePoint site.