SSL/TLS Error Message

Why Wait

I. Error message:

How do I configure SSL/TLS Edge Certificates to remove the following error message:

II. Summary

“Unable to connect with TLS encryption Log data: ++ Starting Swift_SmtpTransport << 220-35-236-118-198.cprapid.com ESMTP Exim 4.96 #2 Sun, 13 Aug 2023 23:37:58 -0700 220-We do not authorize the use of this system to transport unsolicited, 220 and/or bulk e-mail. >> EHLO mautic.devced.com << 250-35-236-118-198.cprapid.com Hello mautic.devced.com [35.236.118.198] 250-SIZE 52428800 250-8BITMIME 250-PIPELINING 250-PIPECONNECT 250-AUTH PLAIN LOGIN 250-STARTTLS 250 HELP >> STARTTLS << 220 TLS go ahead !! Unable to connect with TLS encryption (code: 0)
++ Starting Swift_SmtpTransport << 220-35-236-118-198.cprapid.com ESMTP Exim 4.96 #2 Sun, 13 Aug 2023 23:37:58 -0700 220-We do not authorize the use of this system to transport unsolicited, 220 and/or bulk e-mail. >> EHLO mautic.devced.com << 250-35-236-118-198.cprapid.com Hello mautic.devced.com [35.236.118.198] 250-SIZE 52428800 250-8BITMIME 250-PIPELINING 250-PIPECONNECT 250-AUTH PLAIN LOGIN 250-STARTTLS 250 HELP >> STARTTLS << 220 TLS go ahead !! Unable to connect with TLS encryption (code: 0).”

Step-by-step summary of the provided log data:

  1. Server Greeting: The SMTP client initiates a connection with the server (220-35-236-118-198.cprapid.com) and receives a greeting message indicating the server’s identity, version (Exim 4.96), and timestamp (Sun, 13 Aug 2023 23:37:58 -0700).

  2. Authorization Notice: The server informs that it does not authorize the use of the system for unsolicited or bulk email.

  3. EHLO Command: The client sends the EHLO command along with its domain (mautic.devced.com) to introduce itself to the server.

  4. Server Response: The server responds, acknowledging the client’s domain and providing a list of supported features, including message size, MIME encoding, pipelining, authentication methods (PLAIN LOGIN), STARTTLS support, and general help.

  5. STARTTLS Command: The client attempts to initiate a secure TLS-encrypted connection by sending the STARTTLS command.

  6. Server Response: The server responds with a confirmation to proceed with TLS encryption (220 TLS go ahead !!).

  7. TLS Connection Error: Despite the server’s approval, the client encounters an issue while trying to establish the TLS-encrypted connection, resulting in an error message: “Unable to connect with TLS encryption (code: 0).”

  8. Reattempt: The SMTP client repeats the same sequence of commands, possibly indicating an attempt to resolve the TLS connection issue.

  9. Duplicate Result: The second attempt also encounters the same TLS connection error (code: 0) while trying to establish encryption.

Detailed Summary Analysis:

The provided log data represents an SMTP communication attempt between an SMTP client (presumably utilizing the Swift_SmtpTransport library) and an SMTP server (220-35-236-118-198.cprapid.com) on Aug 13, 2023. The interaction involves the client introducing itself, the server responding with capabilities, an attempt to initiate a secure TLS-encrypted connection, and a subsequent failure to establish the TLS encryption (code: 0).

Key stages include:

  • Connection initiation with server greeting and authorization notice.
  • Client EHLO command and server’s feature list response.
  • Client’s attempt to enable TLS encryption (STARTTLS) and server’s consent.
  • Unsuccessful TLS encryption due to an unidentified error (code: 0).

As the error repeats in both connection attempts, it indicates a persistent issue. Possible reasons for the TLS connection error remain consistent with the previous analysis: misconfigured server settings, incompatible SSL/TLS libraries, firewall or network restrictions, or problems with the server’s TLS certificate.

This is an SMTP connection - which won’t be going via Cloudflare. So you need to talk to your mail server administrator or hosting provider to configure TLS correctly on that server.

Alternatively, you can configure Cloudflare to proxy mail traffic, but it would be as part of Spectrum on an Enterprise plan only:

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