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Sending Plain Text E-mail Messages

Equal signs at end of lines

 

When I send mail to Internet users, they complain that my text has equals signs at the end of each line. What is this? How can I make it stop?

You are sending your messages in the MIME message format. The Microsoft Internet Mail program sends plain text messages in a MIME format called Content-Transfer-Encoding: Quoted-Printable. The mail header usually shows something similar to:

        Mime-Version: 1.0
        Content-Type: text/plain; charset=iso-8859-1
        Content-Transfer-Encoding: quoted-printable

If you find this bothersome, you have several options. You can keep all of your lines less than 76 characters long, in which case the Internet Mail service provider will not have to insert these soft line break sequences. You can send your mail in a format other than MIME, via the Message Format setting. If your correspondent is using Exchange, you can specify that Exchange send rich text along with the message. Or your correspondent can use a MIME mail reader, which presumably will know how to handle this encoding correctly.

Some e-mail programs, most notably those from Microsoft that use quoted-printable encoding can encode high order ASCII characters using a scheme where the equal sign ("=") indicates a character to be decoded followed by the hexadecimal string value of the character to be encoded. This system of course assumes that the client e-mail program can decode these characters (which most can). Things that trigger automatic quoted-printable encoding:

1. High order characters - characters with the following ordinal values 0..31,61,128..255
2. Long lines in a message body (you can turn wordwrap on to fix this)

If your message contains extended characters coded in quoted-printable format your e-mail client may append the following preamble to your message:

Sender composed mail containing characters not in the US-ASCII set
These characters have been transformed into a printable form.

This is identified in the mail header under the Content-Type line similar to:

        Mime-Version: 1.0
        Content-Type: text/plain; charset=iso-8859-1
        Content-Transfer-Encoding: quoted-printable

To correct this, change your default character set from ISO 8859-1 to US ASCII, or else take any of the precautions listed above. For more information, see the Knowledge Base articles Q146629 (Microsoft Exchange Internet Mail Lines End with a "=") and Q168779 OLEXP: No Quote Characters When Using Quoted Printable Format . The mail headers should then show:

        Content-Type: text/plain; charset=us-ascii

Note that the Exchange Server Internet Mail Connector (IMC) only encodes content this way on multipart MIME messages. When the IMC processes a message lacking extended characters or attachments, it instead hard wraps the plain text.

 

Original material courtesy of Gerald E. Boyd.