Upon attempting to archive an existing Owners Package, I receive the following error message, and the package fails to archive, staying active instead.

Unhandled Exception ("PhabricatorDataNotAttachedException")

Attempting to access attached data on PhabricatorOwnersPackage (via getPaths()), but the data is not actually attached. Before accessing attachable data on an object, you must load and attach it.

Data is normally attached by calling the corresponding needX() method on the Query class when the object is loaded. You can also call the corresponding attachX() method explicitly.