We are doing Standard MAC by trying to Delete a Unity account for an End User no longer with the Company. When we try and delete, we get a Pop-up Window, that states "Substitute Objects have not yet been configured on the this Unity Server". Deleting this Subscriber if it owns or is referenced by a Call Handler, could cause database errors" . "You can either cancel the Deletion and confgure Substitute Objects, or proceed with the delete and run DBwalker to identify any database errors". What are we encountering, and what is the best work around?