Sendmail: DSN: servizio non disponibile

Ho avuto difficoltà a trovare il mio server per submit e-mail e non ho per la vita di me capito come risolvere il problema. Se qualcuno mi potesse dare alcuni semplici suggerimenti, sarebbe molto apprezzato!

May 19 15:36:03 ubuntu-12 sm-mta[2484]: s4JFa3jp002484: from=<www-data@ubuntu-12.04- production>, size=412, class=0, nrcpts=1, msgid=<201405191535.s4JFZw4c002483@ubuntu-12.04- production>, proto=ESMTP, daemon=MTA-v4, relay=ip6-localhost [127.0.0.1] May 19 15:36:03 ubuntu-12 sendmail[2483]: s4JFZw4c002483: to=myname@mycompany.com, ctladdr=www-data (33/33), delay=00:00:05, xdelay=00:00:05, mailer=relay, pri=30123, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (s4JFa3jp002484 Message accepted for delivery) May 19 15:36:03 ubuntu-12 sm-mta[2487]: s4JFa3jp002484: to=<myname@mycompany.com>, ctladdr=<www-data@ubuntu-12.04-production> (33/33), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=120412, relay=mailserver.mycompany.com. [213.171.216.115], dsn=5.0.0, stat=Service unavaila$ May 19 15:36:03 ubuntu-12 sm-mta[2487]: s4JFa3jp002484: s4JFa3jp002487: DSN: Service unavailable May 19 15:36:03 ubuntu-12 sm-mta[2487]: s4JFa3jp002487: to=<www-data@ubuntu-12.04-production>, delay=00:00:00, xdelay=00:00:00, mailer=local, pri=30000, dsn=2.0.0, stat=Sent 

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