This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: gaetsejm@eskom.co.za host mx1.eskom.seagatestoragecloud.co.za [169.239.240.92] SMTP error from remote mail server after RCPT TO:: 550-Callout verification failed: 550 550 5.1.1 User unknown gad@cybersmart.co.za host mail3.mx.cybersmart.co.za [196.41.127.11] SMTP error from remote mail server after end of data: 550 High probability of spam Gadifelen.Fabtravel@Galileosa.co.za host mail-gw2.pccc.co.za [3.64.82.161] SMTP error from remote mail server after RCPT TO:: 550 5.1.1 : Recipient address rejected: undeliverable address: host 196.22.216.144[196.22.216.144] said: 550 5.1.1 : Recipient address rejected: User unknown in virtual mailbox table (in reply to RCPT TO command) Gaelebale.Shingange@tsogosun.com host za-smtp-inbound-2.mimecast.co.za [41.74.193.210] SMTP error from remote mail server after RCPT TO:: 550 Administrative prohibition - envelope blocked - https://community.mimecast.com/docs/DOC-1369#550 [87IWBE6RMdufhJN4Im_Qtw.za23] gadija@mweb.co.za host securemail-mx3.synaq.com [196.35.198.130] SMTP error from remote mail server after RCPT TO:: 550-rejected because 13.251.197.89 is in a black list at combined.abusix.dnsbl 550 https://lookup.abusix.com/search?q=13.251.197.89 GADDISON@CYBERTRADE.CO.ZA all hosts for 'cybertrade.co.za' have been failing for a long time (and retry time not reached)