SAP Message USC527 - Mail inbox: The address type of the sender is not supported

Diagnosis Inbox SEM-SRM: The sender of the send request is of type &v1&. Thisaddress type is currently not supported. System Response The inbound processing is canceled. Instead, standard delivery is madeto the normal inbox (transaction SBWP). Procedure Use the transaction SBWP to read the newly arrivedmail there. Notify your system administrator.