msg: system failure: MessagingException
code: service.FAILURE
method: ZmCsfeCommand.prototype.invoke
detail: soap:Receiver


here is /var/log/mail.log

Sep 19 07:38:30 ns1 postfix/postqueue[9990]: fatal: Queue report unavailable - mail system is down
Sep 19 07:39:00 ns1 postfix/postqueue[10082]: fatal: Queue report unavailable - mail system is down
Sep 19 07:39:31 ns1 postfix/postqueue[10152]: fatal: Queue report unavailable - mail system is down
Sep 19 07:40:00 ns1 postfix/postqueue[10215]: fatal: Queue report unavailable - mail system is down
Sep 19 07:40:01 ns1 postfix/postqueue[10266]: fatal: Queue report unavailable - mail system is down
Sep 19 07:40:06 ns1 zmmailboxdmgr[10505]: status requested
Sep 19 07:40:06 ns1 zmmailboxdmgr[10505]: status OK
Sep 19 07:40:30 ns1 postfix/postqueue[10602]: fatal: Queue report unavailable - mail system is down
Sep 19 07:41:00 ns1 postfix/postqueue[10620]: fatal: Queue report unavailable - mail system is down
Sep 19 07:41:30 ns1 postfix/postqueue[10707]: fatal: Queue report unavailable - mail system is down
Sep 19 07:42:00 ns1 postfix/postqueue[10726]: fatal: Queue report unavailable - mail system is down
Sep 19 07:42:05 ns1 zmmailboxdmgr[10878]: status requested
Sep 19 07:42:05 ns1 zmmailboxdmgr[10878]: status OK
Sep 19 07:42:30 ns1 postfix/postqueue[10984]: fatal: Queue report unavailable - mail system is down
Sep 19 07:43:00 ns1 postfix/postqueue[11006]: fatal: Queue report unavailable - mail system is down
Sep 19 07:43:30 ns1 postfix/postqueue[11094]: fatal: Queue report unavailable - mail system is down
Sep 19 07:44:00 ns1 postfix/postqueue[11111]: fatal: Queue report unavailable - mail system is down
Sep 19 07:44:05 ns1 zmmailboxdmgr[11276]: status requested
Sep 19 07:44:05 ns1 zmmailboxdmgr[11276]: status OK