[Coral-List] tech tips two, attaching images

Mike Jankulak mike.jankulak at noaa.gov
Wed Aug 10 09:29:02 EDT 2011

I thought I would mention one other problem that seems to come up with
Coral-List postings rather frequently, that of binary attachments.

Coral-List is set up to be strictly plain-text.  This is perhaps overly
conservative but it is the most secure setting that requires the least
amount of oversight by moderators.  HTML-format email (you are probably
using this if your message window allows you to use italics, bold or
colored text, different fonts, bullet points or other fancy formatting)
is converted to plain text automatically by the mailing list software.
Many attachments can be stripped out before posting.

However, sometimes the mailing list software cannot separate an image
from the rest of the message.  In at least some cases this is because
the poster's software uses a content-type called "multipart/related"
which basically says the the message content must be considered as a
whole and its constituent parts cannot be separated.  In this case the
software must strip out the entire message and rather than post a blank
message to the list, it alerts the moderators that this has occurred. At
that point we contact the poster and suggest reposting without any images.

One "gotcha" is that often the images that cause the most trouble are
those that are in a poster's signature file.  These might be
organizational logos, event promotions, or (as in one recent case)
digitalized signatures.  The poster isn't consciously trying to send an
image to a Coral-List post but their signature file might cause message
rejection anyhow.

The safest bet is never to include any images (or other binary
attachments including PDFs, spreadsheets, formatted documents) in your
message.  If you want to share such materials with the list you can
generally find a way to upload it to a file-sharing site and then just
send its link to the list.

Again, this is a fairly common phenomenon so please don't feel singled
out if this has happened to you recently, you are in good company.

Mike Jankulak, coral-list moderation team

Mike Jankulak, Research Associate, University of Miami / CIMAS
   NOAA / Atlantic Oceanographic Meteorological Laboratory
 4301 Rickenbacker Causeway, Miami, FL 33149 -- 305-361-4543

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