To master your e-mail, make sure your server has the right settings
This is the summer practically every
agency is upgrading mail servers. Many users are just discovering fancy new e-mail options
and mailing unreadable messages.
Last issues column discussed ways to merge address books and store messages from
multiple mail accounts. Now lets take a look at two e-mail transmission problems on
First, why does mail sent to your site sometimes bounce and, conversely, why
doesnt the mail you address correctly always get through?
Second, why does some mail arrive formatted in ways you cant read?
Lets start with bounced mail. If it cannot pass between two points, chances are
one site has an incorrectly configured mail server.
The text address you type gets translated by the Internets Domain Name System
into a numeric IP address. Name servers on your network and elsewhere are programmed to
map individual host names to the IP addresses.
A properly configured local name server has an internal name resolver that recognizes
and routes incoming messages. It tracks all local IP addresses, the host names of the
Internets regional root zone servers and details about recently resolved addresses
Your local server should be configured to recognize and pass DNS Mail Exchange (MX)
records. MX has been the Internet standard for a few years, but some locations have never
implemented it properly.
Chances are your local mail handler is configured correctly, so the difficulty might be
that its not set to receive nonstandard mail. This is a big world. Sites should
support as many mail protocols as they can.
If your system is set to look first for an address record, known as an A record, it
might not even attempt to find the MX record. The A record defines the host name-to-IP
address mappings, and there should be one A record for every host and IP address
combination. Although its technically incorrect to use an A record for mail, some
You can eliminate many glitches by making sure your mail system uses MX records on all
outgoing mail. Check the configuration options to see whether you can correct incoming
mail that does not follow the rules. Accept A record lookups if you can.
For mail-related DNS questions, monitor the Usenet newsgroup
Unreadable messages stem directly from the many formatting options available on mail
readers. Many people automatically put Hypertext Markup Language tags in their mail to add
background colors, special fonts and graphics. These can get garbled in transit,
particularly if they pass through a list server for mail list distribution.
In some cases, a background color alone will render a message unreadable, even if most
other HTML tags get through unharmed.
To ensure legible messages, do not use HTML in any mail sent to a listserv computer,
advised Greg Gunther, a technical support volunteer for a mail list I subscribe to.
Gunther gave me these suggestions for disabling HTML on some common mailers:
Below are other options under the heading Encode Using. Select None. That means you can
read MIME but not send it out. You can also set the mailers to wrap characters
automatically at 76 spaces.
When it comes to sorting mail problems, stick to the basics. That doesnt mean you
cant get as fancy as you like with internal mail. But in dealing with the great
Internet unknown, keep things simple to get your message across.
Shawn P. McCarthy is a computer journalist, webmaster and Internet programmer for
Cahners Business Information Inc. E-mail him at firstname.lastname@example.org.