Unable to load https://<machine name>/arcgis/apps/mapviewer/... status: 404

Error Message

When creating an offline area in Portal for ArcGIS Map Viewer or ArcGIS Field Maps within an ArcGIS Enterprise environment, the following error message is returned:

Error:
Unable to load https://<machine name>/arcgis/apps/mapviewer/undefined/SetupMapArea/submitJob?... status: 404

Cause

The federated ArcGIS Server is not configured as the hosting server. Without the hosting server role, the server does not provide the required capabilities or service endpoints that Portal for ArcGIS uses to create offline map areas. A hosting server is required for publishing and managing hosted services, as well as supporting workflows such as taking maps offline. For more information on functions available through integration with a hosting server, refer to Portal for ArcGIS: Functions available through integration.

Solution or Workaround

Note:
This workflow requires administrator privileges.

Ensure the ArcGIS GIS Server site is licensed as an ArcGIS GIS Server (Standard or Advanced edition) and federated with the portal, then designate it as the portal's hosting server. Refer to Portal for ArcGIS: Specify the hosting server for instructions and ArcGIS Server: ArcGIS GIS Server capabilities and extensions for more information.