Re: ListServ MLM refuses Squirrelmail plain text messages

Paul Lesniewski <[email protected]>
Newsgroups gmane.mail.squirrelmail.user
Message-ID <[email protected]>

On 2018年05月24日 12:14, James B. Byrne via squirrelmail-users wrote:
> 
> On Thu, May 24, 2018 14:40, James B. Byrne wrote:
>>
>> Starting this morning (2018-05-2) my Squirrelmail (SM) composed posts
>> to a Listserv mailing list service are being bounced back with this:
>>
> . . .
>> Does anyone have a clue as to what is happening and how it is
>> resolved?
>>
> 
> The temporary fix is to attach an empty or proforma content file to
> the message and send.  This causes the missing header to be created:
> 
> Content-Type: text/plain; charset="iso-8859-1"

This header is not the cause.  It's a problem with one of the servers in
the receiving chain not supporting 8-bit MIME messages while the initial
server indicates that it has 8-bit MIME support.  Not a SquirrelMail
issue in any way, shape or form.

https://clintboessen.blogspot.com/2011/10/smtp.html
https://knicksmith.blogspot.com/2007/07/ndr-message-561-body-type-not-supported.html
https://groups.google.com/forum/#!topic/microsoft.public.exchange.admin/DZE9Hkd-Dvc
https://www.roundcubeforum.net/index.php?topic=6276.0
https://social.technet.microsoft.com/Forums/office/en-US/89abe56e-bebf-4b66-b235-9bbd3efb02fa/body-type-not-supported-errors?forum=exchangesvradminlegacy
https://johanveldhuis.nl/554-561-body-type-not-supported-by-remote-host/
http://forums.msexchange.org/Body_type_not_supported_by_Remote_Host/m_10083700/tm.htm

$ telnet outlook.com 25
Trying 40.97.153.146...
Connected to outlook.com.
Escape character is '^]'.
220 BN6PR2001CA0009.outlook.office365.com Microsoft ESMTP MAIL Service
ready at Thu, 14 Jun 2018 09:29:15 +0000
EHLO example.com
250-BN6PR2001CA0009.outlook.office365.com Hello [111.222.333.444]
250-SIZE 157286400
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-STARTTLS
250-8BITMIME
250-BINARYMIME
250-CHUNKING
250 SMTPUTF8

James, in your specific example, the mail goes through several hops, all
of which seem to be hosted by Microsoft's servers, and I suspect those
are probably OK.  The last hop is to the organization hosting the
mailing list and it's probably the culprit - probably an older or
misconfigured Exchange server or the likes.  I tried to telnet to it to
test its greeting but it would not talk to me.

-- 
Paul Lesniewski
SquirrelMail Team
Please support Open Source Software by donating to SquirrelMail!
http://squirrelmail.org/donate_paul_lesniewski.php

------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
-----
squirrelmail-users mailing list
Posting guidelines: http://squirrelmail.org/postingguidelines
List address: [email protected]
List archives: http://news.gmane.org/gmane.mail.squirrelmail.user
List info (subscribe/unsubscribe/change options): https://lists.sourceforge.net/lists/listinfo/squirrelmail-users
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.