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: asibulali@sars.gov.za 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 [-dLnEbzsNX2conz08xwl0Q.za80] asibanda@cut.ac.za 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 [-dLnEbzsNX2conz08xwl0Q.za80] asibisi@mweb.co.za host securemail-mx3.synaq.com [196.35.198.130] SMTP error from remote mail server after RCPT TO:: 550-rejected because 52.221.55.32 is in a black list at combined.abusix.dnsbl 550 https://lookup.abusix.com/search?q=52.221.55.32 ASibanda@fnb.co.za host mx2.hc858-6.c3s2.iphmx.com [216.71.159.52] SMTP error from remote mail server after DATA: 550 #5.7.1 Your access to submit messages to this e-mail system has been rejected. asibanda@toyfin.co.za host mx2.hc858-6.c3s2.iphmx.com [216.71.157.233] SMTP error from remote mail server after DATA: 550 #5.7.1 Your access to submit messages to this e-mail system has been rejected. asics@cerecam.uct.ac.za all hosts for 'cerecam.uct.ac.za' have been failing for a long time (and retry time not reached)