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  dengran@sf-express.com
    host eMX2.sf-express.com [123.58.60.141]
    SMTP error from remote mail server after RCPT TO:<dengran@sf-express.com>:
    554-Service unavailable; Client host [omr21.orchid.atmailcloud.com] blocked using
    554-Barracuda Reputation;
    554 http://www.barracudanetworks.com/reputation/?r=1&ip=52.221.55.32
  deng@forma.cn
    host hmx146.cn4e.com [47.52.222.213]
    SMTP error from remote mail server after RCPT TO:<deng@forma.cn>:
    550 RC:NE <deng@forma.cn>:The email account does not exist
  denel8.businessandexe@galileosa.co.za
    host mail-gw2.pccc.co.za [3.64.82.161]
    SMTP error from remote mail server after RCPT TO:<denel8.businessandexe@galileosa.co.za>:
    550 5.1.1 <denel8.businessandexe@galileosa.co.za>:
    Recipient address rejected: undeliverable address:
    host 196.22.216.144[196.22.216.144] said: 550 5.1.1 <denel8.businessandexe@galileosa.co.za>:
    Recipient address rejected: User unknown in virtual mailbox table (in reply to RCPT TO command)
  DeneseP@nbl.co.za
    host za-smtp-inbound-2.mimecast.co.za [41.74.197.201]
    SMTP error from remote mail server after RCPT TO:<DeneseP@nbl.co.za>:
    550 sip.invaluement.mimecast.org Blocked by ivmSIP and/or ivmSIP/24 - see https://www.invaluement.com/lookup/?item=52.221.55.32. - https://community.mimecast.com/docs/DOC-1369#550 [FDYhyPOmNc2bA3LikyDVdA.za2]
  denby@science.uct.ac.za
    host za-smtp-inbound-2.mimecast.co.za [41.74.197.201]
    SMTP error from remote mail server after RCPT TO:<denby@science.uct.ac.za>:
    550 sip.invaluement.mimecast.org Blocked by ivmSIP and/or ivmSIP/24 - see https://www.invaluement.com/lookup/?item=52.221.55.32. - https://community.mimecast.com/docs/DOC-1369#550 [FDYhyPOmNc2bA3LikyDVdA.za2]
  deneau.celine@wanadoo.fr
    host smtp-in.orange.fr [193.252.22.65]
    SMTP error from remote mail server after end of data:
    550 5.2.0 ra77mgQy74ngv Mail rejete. Mail rejected. OFR_506 [506]
  denekewa@un.org
    host unasav8.un.org [85.159.201.189]
    SMTP error from remote mail server after initial connection:
    554-unasav8.un.org
    554 Rejected
  denaidoo@cisco.com
    host alln-mx-01.cisco.com [173.37.147.230]
    SMTP error from remote mail server after DATA:
    550 Connections from omr21.orchid.atmailcloud.com (52.221.55.32) are being rejected due to a poor email reputation score. The sender should have their email support team review https://talosintelligence.com/reputation_center/lookup?search=52.221.55.32 . Once the source of the poor reputation has been fixed, the score will begin to increase and this system will automatically start accepting connections again.