TLS is required, but was not offered by host

  • Hi,

    I am getting following error message while sending emails to some domains.

    "TLS is required, but was not offered by host"

    In postfix log I am getting following :

    86F8C36C0816: to=<>,[]:25, delay=5.1, delays=0.38/0.22/4.5/0, dsn=5.7.4, status=bounced (TLS is required, but was not offered by host[])

    I found solution on iRedMail forum to set : "-o smtp_tls_security_level=none" in postfix configuration "/etc/postfix/": but this will practically disable security.

    Can You help me please?

    Kind regards,


  • Did you enable "Enforce TLS outgoing" for the Mailbox? (Login to mailcow UI with the email-address to check.)

    Or did you configure any "TLS policy maps" ?

    Thank You for a hint.:)

    Heavgale - indeed someone turn this settings on and clearly didnt know what consequences it brings! THANK YOU. It seems this solve the issue!