Conference chefs::ms-exchange

938.0. "Attachments not readable? ENCODE/DECODE issue" by MEOC02::BEESTONL (Liz Beeston) Tue Mar 18 1997 08:35

    Hi,
    I am configuring an IMC on a customer system. To test internet mail and
    attachment handling I have sent some mail to my Digital Exchange
    account. [email protected]
    
    The customers IMC is set to 'Send Attachments Using' MIME and when I
    created the message I specified that the 'Send Options Attachment
    Format' to be MIME.
    
    The message is delivered to me at [email protected] but I cannot
    read the attachments.
    The filenames of the attachments have been preserved, (presumably by
    Exchange TNEF) and the correct application icons are displayed. When I
    open the attachment, it looks like it has not been decoded but there
    are not the usual MIME headers at the top of the information displayed.
    Attachment was a WORD document and an EXCEL spreadsheet.
    
    (I get exactly the same result if I send the attachments as UUENCODED)
    
    I had expected the attachment encoding/decoding to work correctly as it
    is Exchange IMC to Exchange IMC. 
    
    I have added the RFC headers from the message received at Digital
    below. In the header there is some text which doesn't seem correct -
    'This message is in MIME format. Since your mail reader does not
    understand this format, some or all of this message may not be
    legible.' 
    
    I have the default IMC MIME Types config on the sending Exchange
    Server.
    
    Does anyone know what may be wrong with the config that is preventing
    correct MIME encode/decode?
    
    Thanks, Liz 
    
    
    RFC 822 Headers from received message (@mail.dec.com)
    =====================================================
    Received: from mail12.digital.com by mrohub1.mro.dec.com with SMTP
    (Microsoft Exchange Internet Mail Connector Version 4.0.994.63)
    	id GJATZMHB; Tue, 18 Mar 1997 00:43:21 -0500
    Received: from gatekeeper.alfred.org.au by mail12.digital.com
    (8.7.5/UNX 1.5/1.0/WV)
    	id AAA23469; Tue, 18 Mar 1997 00:39:26 -0500 (EST)
    Received: from ehcn9.alfred.org.au by gatekeeper.alfred.org.au;
    (5.65v3.2/1.1.8.2/04Mar97-0200PM)
    	id AA02353; Tue, 18 Mar 1997 16:39:32 +1000
    Received: by ehcn9.alfred.org.au with SMTP (Microsoft Exchange Server
    Internet Mail Connector Version 4.0.994.63)
    	id <[email protected]>; Tue, 18 Mar 1997
    16:39:36 +1000
    Message-Id:
    <c=AU%a=_%p=IEHCN%[email protected]>
    From: "Beeston, Liz" <[email protected]>
    To: "'[email protected]'" <[email protected]>
    Subject: test 7 from alfred exchange to digital exchange MIME
    attachments
    Date: Tue, 18 Mar 1997 16:39:34 +1000
    X-Mailer:  Microsoft Exchange Server Internet Mail Connector Version
    4.0.994.63
    Mime-Version: 1.0
    Content-Type: multipart/mixed; boundary="----
    =_NextPart_000_01BC33BA.F746B0B0"
    
    This message is in MIME format. Since your mail reader does not
    understand
    this format, some or all of this message may not be legible.
    
    ------ =_NextPart_000_01BC33BA.F746B0B0
    Content-Type: text/plain; charset="us-ascii"
    Content-Transfer-Encoding: 7bit
    
    ------ =_NextPart_000_01BC33BA.F746B0B0
    Content-Type: application/octet-stream; name="mailtest.xls"
    Content-Transfer-Encoding: base64
    
    ------ =_NextPart_000_01BC33BA.F746B0B0
    Content-Type: application/msword; name="mailtest.doc"
    Content-Transfer-Encoding: base64
    
    ------ =_NextPart_000_01BC33BA.F746B0B0--
    
    =================//// end of RFC 822 haders ////==================

The fact that you see the icons and correct filenames suggests
that your IMC did encode the files in MIME format and that
our IMC decoded them.

The message you see in the RFC 822 headers,
    'This message is in MIME format. Since your mail reader does not
    understand this format, some or all of this message may not be
    legible.' 
is what is displayed to someone who does not have a MIME-capable
reader.  If you had a problem decoding, that would have been at
the top of the message in the text window.

Any chance you're suffering from version skew - e.g. you created
the documents in Office 97 and are trying to read in Office 95
programs?

>> Any chance you're suffering from version skew - e.g. you created
>> the documents in Office 97 and are trying to read in Office 95
>> programs?
    
    There is a big chance that I am suffering from version skew. This was
    exactly the problem.
    
    But if I was reading this message at Digital with my Exchange client
    why did I get the message about the '...your mail reader does not
    understand this format...' ?
    Is this added to the message before the receiving Exchange IMC decodes 
    the message/attachments.
    
    Thanks ..Liz

Exchange puts the text about being MIME-encoded when it
sends the message (most likely while doing the MIME-encoding
of the attachments).  It's put in before the first bodypart,
so readers which understand MIME don't display it (though
in Exchange, at least, it is visible when you look at
the RFC822 headers, as you've seen).

You didn't see the warning text in your message window
because Exchange recognized the MIME header and went
on to decode and show you the actual bodyparts.  If using
a reader that did not understand MIME, the warning text would
be the first paragraph in the message (and the rest of the
message would be a bunch of characters separated by the
MIME boundaries:
    ------ =_NextPart_000_01BC33BA.F746B0B0
    Content-Type: text/plain; charset="us-ascii"
    Content-Transfer-Encoding: 7bit

As you've seen, just because Exchange can decode (from the
ASCII encoding required by Internet Mail to the binary document
format of Word, Excel, JPG...) the bodyparts does not mean that
you can read them (you must have the correct viewer, supporting
the right versions...)