Why ORF does not block foo@bar when it is on the sender blacklist?
First, please check the ORF logs regarding this given sender, it may have been whitelisted. It is also possible that you do not find the sender in the logs and you can match the email by the recipient and the arrival time only. Why? Because ORF identifies the sender and recipient as the SMTP envelope sender and recipient. Emails are similar to the real life postal mails. You put your letter into an envelope and write the sender and the recipient to the envelope. The post office delivers your mail to the recipient on the envelope, they do not open your envelope and check who is the sender and recipient on the letter paper. Emails also have envelope sender and recipient (they are called SMTP envelope sender and recipient) and letter sender and recipient (called MIME sender and recipient). Your email client, like Outlook displays the MIME sender and recipient only. Actually, the envelope sender and recipient is not stored in the email anywhere. * The SMTP envelope and MIME envelope inform
