ERROR 001784: Unable to connect to the database used for scene caches (unauthorized)

Error Message

When attempting to publish a scene service from ArcGIS Pro, publishing may succeed while the scene cache status reports showing "Failed" or "Unknown".

The following error is returned in the ArcGIS Server logs:
"ERROR 001784: Unable to connect to the database used for scene caches (unauthorized)."

Cause

If the error message exists in the ArcGIS Server logs, the issue is related to communication via cookies between the ArcGIS Data Store and ArcGIS Server. The ArcGIS Data Store uses cookies to authenticate communication; the cookie policy set on ArcGIS Server Windows machine may block this.

Initially, the scene caching tools use an internet URL to connect to the scene cache database. In this case, internet policies apply.

If the internet connection fails, the tools attempt to connect using an intranet URL, in which case intranet policies apply. To verify that the URLs used by the tools are correctly set up to access the scene cache database, confirm that the ArcGIS Data Store host names are correct, and update cookie policies on the ArcGIS for Server machines.

Solution or Workaround

1. Open a web browser and log in to the ArcGIS Server site's Administrator Directory. Log in using ArcGIS Server administrator credentials.
2. Navigate to:

data > items > nosqlDatabases > /nosqlDatabases/AGSDataStore_nosqldb_ <database name> > REST

Additionally, add the URL of the unqualified host name as a trusted site, for example: 'datastore'.

3. Take note of the 'hostname' and 'unqHostname' properties. These are the fully qualified domain name and unqualified domain name of the scene cache database. They will be used later when updating cookie policies.
4. Log in to each ArcGIS Server machine using the ArcGIS Server account. This is the account created to run ArcGIS Server processes when ArcGIS Server is installed.
5. Access the machine's Internet Options. This can be accessed through Internet Explorer or the Control Panel.
6. Click the Security tab, select Trusted sites > Sites, and add the URL for the fully qualified host name of the scene cache database, for example: 'datastore.domain.com'.
7. Click OK to apply the changes, and close Internet Options.
8. Restart ArcGIS Server.
9. Repeat the steps for every ArcGIS Server machine available onsite.