CheckTLS TestSender FAILED

Below are the details from your CheckTLS TestSender test from <info@domain.de> via [230.175.195.38] run on 2015-04-15 12:22:26 EDT. 
Original email Subject: sx9zf6sdcvdkv

Your email was sent, however it was NOT SENT SECURELY using TLS.

A transcript of the eMail SMTP session is below:
--> this would be a line from your email system to our test
<-- and this would be a line to your email system from our test

If TLS was negotiated, a line is added:
====tls negotiation successful (cypher: cyphername, client cert: certinfo)

Everything after that line is secure (encrypted), as indicated by:
~~> commands from your system then have wiggly lines
<~~ and responses from our system do too

Any errors that the test noticed are noted in the log by asterisk boxes:
***************************************
*** ********** Error Note ********* ***
***                                 ***
*** The error message would be here ***
***                                 ***
***************************************
***************************************

___TRANSCRIPT BEGINS ON THE NEXT LINE___
<-- 220 ts3.checktls.com CheckTLS TestSender Wed, 15 Apr 2015 12:22:25 -0400
--> EHLO mail.domain.de
<-- 250-ts3.checktls.com Hello mail.domain.de [230.175.195.38], pleased to meet you
<-- 250-ENHANCEDSTATUSCODES
<-- 250-8BITMIME
<-- 250-STARTTLS
<-- 250 HELP
--> MAIL FROM:<info@domain.de> BODY=7BIT
<-- 250 Ok - mail from info@domain.de
--> RCPT TO:<test@TestSender.CheckTLS.com>
<-- 250 Ok - recipient test@TestSender.CheckTLS.com
--> DATA
<-- 354 Send data.  End with CRLF.CRLF
--> Received: from localhost (localhost [127.0.0.1])
--> 	by mail.domain.de (Postfix) with ESMTP id A7002340082
--> 	for <test@TestSender.CheckTLS.com>; Wed, 15 Apr 2015 18:22:24 +0200 (CEST)
--> X-Virus-Scanned: Debian amavisd-new
--> Received: from [192.168.0.91] (ip5b584483.dynamic.kabel-deutschland.de [65.458.52.131])
--> 	by mail.domain.de (Postfix) with ESMTPSA id 9222234007C
--> 	for <test@TestSender.CheckTLS.com>; Wed, 15 Apr 2015 18:22:23 +0200 (CEST)
--> Message-ID: <552E9040.2080603@domain.de>
--> Date: Wed, 15 Apr 2015 18:22:24 +0200
--> From: t <info@domain.de>
--> User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0
--> MIME-Version: 1.0
--> To: test@TestSender.CheckTLS.com
--> Subject: sx9zf6sdcvdkv
--> Content-Type: text/plain; charset=utf-8; format=flowed
--> Content-Transfer-Encoding: 7bit
--> 
--> 
--> .
<-- 250 Ok
--> QUIT
<-- 221 ts3.checktls.com closing connection