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  GRP-TFR-PETenders@transnet.net
    host za-smtp-inbound-1.mimecast.co.za [41.74.193.201]
    SMTP error from remote mail server after end of data:
    554 Email rejected due to security policies - https://community.mimecast.com/docs/DOC-1369#554 [CFQfUBHQOVOy-Mt3M-sA5A.za15]
  grp@cyberhost.co.za
    host mail.cyberhost.co.za [196.41.123.124]
    SMTP error from remote mail server after RCPT TO:<grp@cyberhost.co.za>:
    550 No Such User Here"