is Explicit TLS the same as STARTTLS

Could you please confirm for SMTP is Explicit TLS is the same as STARTTLS over port 25
we need to check urgently 
 

Yes, they are the same but they used for different reason.

In practice that means a connection starts as plaintext and then upgrades to TLS encryption after issuing the STARTTLS command.

STARTTLS over port 25 is used for server-to-server SMTP communication, not client submission.
For client submission, port 587 (SMTP Submission) with STARTTLS is preferred.

Are you having some issues?


 

This means a "Command" / "Script" is required to issue / upgrade the call with STARTTLS
Can we have a sample of a command / script Please

No our software does it it for you

You can see everything in the log

Information    18/03/2025 19:10:24    Sending Email: Send Email
Information    18/03/2025 19:10:24    To: Advanced ETL Processor User <info@etl-tools.com>
Information    18/03/2025 19:10:24    SMTP
Information    18/03/2025 19:10:24    Stat Connected.Information    18/03/2025 19:10:24    Recv : 220 server284.com ESMTP
Information    18/03/2025 19:10:24    Sent : EHLO DBSLAMD
Information    18/03/2025 19:10:24    Recv : mmmm.com
250-STARTTLS
250-PIPELINING
250-8BITMIME
250-AUTH LOGIN PLAIN CRAM-MD5
250 SIZE 0
Information    18/03/2025 19:10:24    Sent : STARTTLS
Information    18/03/2025 19:10:24    Recv : 220 ready for tls
Information    18/03/2025 19:10:24    Sent : EHLO DBSLAMD
Information    18/03/2025 19:10:25    Recv : mmmm.com
250-PIPELINING
250-8BITMIME
250-AUTH LOGIN PLAIN CRAM-MD5
250 SIZE 0
Information    18/03/2025 19:10:25    Sent : MAIL FROM:<info@etl-tools.com>
Information    18/03/2025 19:10:25    Recv : 250 ok
Information    18/03/2025 19:10:25    Sent : RCPT TO:<info@etl-tools.com>
Information    18/03/2025 19:10:25    Recv : 250 ok
Information    18/03/2025 19:10:25    Sent : DATA
Information    18/03/2025 19:10:25    Recv : 354 go ahead
Information    18/03/2025 19:10:25    Sent : From: "Advanced ETL Processor User" <info@etl-tools.com>
Subject: Test
To: "Advanced ETL Processor User" <info@etl-tools.com>
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: 8bit
Date: Tue, 18 Mar 2025 19:10:25 +0000
Information    18/03/2025 19:10:25    Sent : 
Information    18/03/2025 19:10:25    Sent : <p>Data</p>
Information    18/03/2025 19:10:25    Sent : 
Information    18/03/2025 19:10:25    Sent : .
Information    18/03/2025 19:10:25    Recv : 250 ok 1742325025 qp 2694
Information    18/03/2025 19:10:25    Done!
Information    18/03/2025 19:10:25    Success