Forum Discussion
exchange not block mail from sender not-exist :
I have third-party applications like GLPI, exchange accepts emails from non-existent mailboxes, is there a possibility at the reception connector level to block or verify the email sender? (not...
I don't believe this is possible. Email systems weren't originally designed to check that the sender email address is a real person (how would one email system check that a sender in another system is a real person?). It's only now that things like SPF, DKIM etc try to establish whether the sender is legitimate, but they don't actually check that the sender email address is a real person and exists. There are plenty of valid scenarios where the sender address actually doesn't exist in the sender environment.