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Hi ,

I have been having a few issues emailing multiple addresses at one particular domain .

this is the sort of thing I'm getting :

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Sophos Email Appliance

Details retrieved

2015-04-22 13:44:12 mail1 postfix/smtpd[22042]: 2B5B613E84B0_537190CF: client=unknown[removed]
2015-04-22 13:44:12 mail1 postfix/cleanup[14022]: 2B5B613E84B0_537190CF: message-id=<523c34d26578463f8cf9cd6e93a874bc@removed>
2015-04-22 13:44:12 mail1 postfix/qmgr[83237]: 2B5B613E84B0_537190CF: from=<removed>, size=9480, nrcpt=1 (queue active)
2015-04-22 13:44:12 mail1 postfix/smtp[16440]: 2B5B613E84B0_537190CF: to=<removed>, relay=127.0.0.1[127.0.0.1]:10025, delay=0.31, delays=0.01/0/0/0.3, dsn=2.0.0, status=sent (250 OK, sent 5537190C_17881_13574_1 5CF4A13E84F5_537190CB)
2015-04-22 13:44:12 mail1 postfix/qmgr[83237]: 2B5B613E84B0_537190CF: removed
2015-04-22 13:44:12 mail1 milter[17881]: 5537190C_17881_13574_1: msg times: r=0.20s u=0.18s s=0
2015-04-22 13:44:12 mail1 milter[17881]: 5537190C_17881_13574_1: conn times: r=0.30s u=0.18s s=0
2015-04-22 13:44:12 mail1 postfix/backend/smtpd[22316]: 5CF4A13E84F5_537190CB: client=localhost.localdomain[127.0.0.1]
2015-04-22 13:44:12 mail1 postfix/backend/cleanup[22320]: 5CF4A13E84F5_537190CB: message-id=<523c34d26578463f8cf9cd6e93a874bc@removed>
2015-04-22 13:44:12 mail1 postfix/backend/qmgr[83379]: 5CF4A13E84F5_537190CB: from=<removed>, size=9692, nrcpt=1 (queue active)
2015-04-22 13:45:32 mail1 postfix/backend/smtp[24925]: 5CF4A13E84F5_537190CB: conversation with ( domain removed )[removed] timed out while sending end of data -- message may be sent more than once

Having no trouble sending to anywhere else ....

Not sure where to looks next , Any Ideas appreciated !!

Thanks in advance !

Roger