In order to backup external Hard Drives, we recommend creating a new Backup Job from the Backup jobs window (ElephantDrive Menu -> Actions -> Add/Edit Backups).
In the configuration details window for the new backup job, click on the "Add include path" button to add a include path. This will pop up a file-browser window where you can browse the contents of your local and external drives.
On Macs, the external drives can be found under the following folders: System -> Volumes.
Article is closed for comments.