code: 500, messageCode: "CONT_0044", message: "Error invoking service"

Error Message

Attempting to add a layer from the subscriber or premium Living Atlas content to the Portal for ArcGIS map viewer fails with the following error message:

Error:   
The layer, <layer_name>, cannot be added to the map.

Additionally, on the Console tab of the developer tool, the following error message is returned:

Error:   
code: 500, messageCode: "CONT_0044", message: "Error invoking service"

Cause

Portal for ArcGIS is unable to reach the service in the Living Atlas subscriber or premium content. The following are potential causes for the issue:

• The ArcGIS Online account credentials used to access the subscriber or premium Living Atlas content have changed, and must be updated in Portal for ArcGIS.
• The ArcGIS Enterprise components and environments do not have trusted certificates.

Solution or Workaround

Choose a workaround depending on the cause.

• Update the credentials for the subscriber or premium Living Atlas content in Portal for ArcGIS. Refer to Portal for ArcGIS: Update credentials for subscriber and premium content for steps to do this.
• Establish trust between the ArcGIS Enterprise components and environments. Refer to GeoNet: Building Trust within Your Environment Using SSL Certificates for more information.