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: daf@cy.co.za host cy.co.za [209.124.66.8] SMTP error from remote mail server after RCPT TO:: 550 No Such User Here" dag@maties.sun.ac.za host mail2.sun.ac.za [146.232.64.14] SMTP error from remote mail server after RCPT TO:: 550 dafiesher@iqgroup.net host za-smtp-inbound-1.mimecast.co.za [41.74.197.201] SMTP error from remote mail server after RCPT TO:: 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 [i1k6rKlxMGGbE4Jl9j8Bjw.za142] dadwals@vsnl.com all hosts for 'vsnl.com' have been failing for a long time (and retry time not reached)