DLR STATUS
From SMS Wiki
List of DLR Statuses
Status options
• DELIVRD (terminal status)
• ERROR (terminal status)
• FAILED (terminal status)
• REJECTD (terminal status)
• SENT (still in progress - may have been delivered with no DLR)
• UNDELIV (Undeliverable - the message cannot be delivered, will keep trying)
• UNDETRM (Undetermined - keep trying)
• UNIDNTFY (terminal status)
• UNKNOWN (terminal status)
