I have set a mail server using postfix, and I can send and receive email, I have certificate created from letsencrypt, but when I try to test the email from this tool:


In the mail log I see a lot of error:

postfix/smtp[15352]: SSL_connect error to mx1.tools.mxtoolbox.com[]:25: -1
warning: TLS library problem: error:1407741A:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert decode error:s23_clnt.c:769:
9489F3A12F: Cannot start TLS: handshake failure

anyone know how can I fix this problem?


  • How is your mail server configured? Commented Oct 13, 2016 at 2:29
  • What you want know?
    – Piero
    Commented Oct 13, 2016 at 6:03
  • Did you ever fix this?
    – Joel Coel
    Commented Sep 12, 2017 at 22:00


You must log in to answer this question.

Browse other questions tagged .