(In reply to comment #0) > Actual Results: > if an email is sent (either plain or html text) to specific email-addresses, a > return email with an error-code 550 is received instantly: > > "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.
2020-09-25 – [SOGo] Update to 18.104.22.16800925-1 2020-09-24 – [SOGo] Re-enable TLS for internal IMAP connections, enable TLS for internal SMTP connections 2020-09-24 – [Web] Minor fix in quarantine view
Also, when configuring the SMTP tab for the super administrator, saved credentials are automatically inserted. This issue is caused by a defect in Google Chrome 59. As a workaround, use a different browser to configure the external directory connection or the SMTP settings. Number of users invited to Apple VPP at the same time is limited
Mail server administrators can customize bounce code messages. Notes: The traditional SMTP bounce codes are three-digit numbers (e.g., 550). The enhanced bounce codes are three-digits separated by decimal points (e.g., 5.1.1). The tables below are not a definitive list of all available bounce codes, only a representation of the most frequent ones.
CSS listings will have return code 127.0.0.3 to differentiate from regular SBL listings, which have return code 127.0.0.2. SBL Usage. For information on how to use the SBL to protect your mail server or network, see the SBL FAQs. The SBL is used both as a sender IP blocklist and as a URI blocklist (SBL is very effective as a URI blocklist).
Seeing the same bounce message from Small Business Server 2011 which runs Exchange 2010. Nothing has changed on server this week and all emails to me.com are bouncing. st11p00mm-smtpin008.mac.com #550 5.7.1 Success delivery receipts not accepted: <redacted>@me.com ## st11p00mm-smtpin008.mac.com rejected your message to the following e-mail ...
extmail.bigpond.com #<extmail.bigpond.com #5.0.0 SMTP; 558 Message content rejected due to suspected spam. IB703> #SMTP# No problems with other servers/domains. mxtoolbox.com not reporting any issues. Just started yesterday.