Technology Tip of the Month
May, 1997: E-mail Attachments
by Deborah Healey
E-mail is a wonderful means of communication. It lets us make and retain
connections to people in distant places. For most people, composing in a
mail program is almost as easy as using a word-processor -- whole-text
rather than line-by-line editing is available in free or very inexpensive
mail programs for all kinds of computers. (If you're still using Elm or
Unix mail, talk to your computer people about Pine, a free program for
mainframe computers from the University of Washington.)
It's easy to get accustomed to 'painless' e-mail communication, where the
biggest problem is in typing the name of the recipient correctly -- at
least until you've added that person to your electronic address book. And
then someone has the bright idea to send you a little graphic or a
formatted file, and reality hits: you get an e-mail attachment that your
mail program chokes on. You get a message on the order of "Unrecognized
attachment" or an otherwise unintelligible message that includes the
phrase, "This message must be decoded with binhex." What next?
The topic of this month's tech tip is one of my biggest
frustrations, attachments. I've put together some suggestions based on my
experience with trying to send and receive files in different ways, most
notably with the Online Seminar I did last month for Eastern European EFL
A Bit of Background
works to send messages from one type of computer to another
because it uses one of computing's lowest common denominators (at least,
one that's still readable by humans)-- plain text, sometimes referred to
as ASCII text. Each letter in the Roman alphabet is assigned a unique
code, and all operating systems interpret that code in the same way.
(Note: Where you may run into problems is if you or your correspondent
use a non-Roman alphabet that uses an extended version of ASCII text--if
both operating systems don't recognize that extended set of codes, you'll
see some very strange characters on your screen.)
you want to use formatting such as bold or italics, a different font
or point size, or anything other than the most ordinary-looking text,
your word-processor is adding additional, usually hidden, characters to
your document. These fall outside the set of codes used by plain text and
therefore have to be translated--encoded-- and sent as a separate but
attached message for electronic transmission. The same thing goes for
graphics, sound, and video files, since they're not plain text either.
Therein lies the rub: if your mail program encodes these attached files
in a way that my mail program doesn't recognize, we have a problem.
- MIME: Multipurpose Internet Mail Extensions, MIME is a way of
encoding an email message that is recognized by many mail programs. In
its most sophisticated versions, MIME lets you put just about anything
into an e-mail message, including graphics, sound, and video. If we ever
do have painless attachments, it may be due to MIME. Unfortunately, not
all mailers incorporate MIME at the same level. I've found the
MIME-encoded messages that my mailer didn't automatically interpret some
of the most difficult to deal with.
- binhex: Attachments sent from Macintosh computers generally
use a binhex format. That's the Macintosh way.
- unzip/zip: Attachments sent from DOS or Windows computers
often use a zip format. It's not entirely predictable, and that's the
- UUdecode/UUencode: This is the usual Unix format. You can tell
because it's got a very strange, non-English-sounding name. It's
The Good News
good news is that, once you get over your initial surge of dismay and
download the translation software you need, you can usually transform
your attachments into something that your computer will understand.
- Get a copy of the appropriate translator. There are a number of
programs available, and you can find more than my brief list here by
searching the web for 'binhex,' 'zip,' or 'uuencode.' Stuffit Expander is
a free all-purpose program from Aladdin Systems that works pretty well,
and is now available in both Macintosh and Windows versions. It often
comes with Netscape Navigator, so you may have a copy already.
- Save the attachment to disk on a desktop machine, or Export it if
you're using Pine. If someone has done you no favor and has
included a binhexed or uuencoded message within a regular mail message,
you'll usually need to take off everything in the message before the
phrase "(This message must be decoded with binhex)" or "This is a
uuencoded message," then save the rest to disk. You can try it without
doing the cutting first, but if the translator doesn't work, you'll need
to go back into the message and excise the offending portion.
- Run the translator, selecting the saved/exported file as your target.
- The test--see if you can now read the file. Remember that if it's a
formatted word-processed document, graphic, sound file, or video clip,
you will need the appropriate software to be able to read, view, or
listen to what you've translated. Open the application you think will
work first, then try opening the file if it's not in a format that you're
sure you recognize. As a fallback, PageMaker is very good at reading a
variety of word-processor and graphics files, and Netscape or Internet
Explorer may have the tools you need to read a sound file or video clip.
Whew. That's why I ask my students to send me their homework not as
an attachment, but by copying the text within their word-processor, then
pasting it into an e-mail message. It's not nearly as pretty, but it's a
lot less work for me to open and read. If you'd like more information on
the subject of attachments, try
a basic primer on binary attachments in e-mail,
lengthy explanation of attachments and different formats.
A caveat: many mail programs cannot handle large files (a 256K
limit is not unusual), and many people have size limits on their
mailboxes. Before you e-mail a wonderful but very large sound or video
clip to someone, check with them about it. If you have a website, it may
be easier for them to download it from the web than to get it as an
If you have questions, comments, or for more information,
contact Deborah Healey, dhealey AT uoregon DOT edu
updated 26 June, 2009