Deleted mailboxes in child domain are not automatically disabled store management by the Active Directory Connector Service.
Issue fixed in version 4.4.2. The latest version of Archive Manager can be downloaded at: http://support.quest.com/Search/SearchDownloads.aspx
Resolved issue in the Archive Manager 4.4.2 release notes:
CR 92146 The Active Directory Connector does not use the correct atrribute when searching for deleted users.