Using Filters in Eudora -- to fight spam and to manage your mail more efficiently

Manfred Kuechler

Using Filters in Eudora -- to fight spam and to manage your mail more efficiently

Version: 19 December 2003

Eudora (current version 5.2.1) is an e-mail program ("client") to manage your e-mail for which Hunter has a site license covering unlimited home and office use by faculty and staff. If you want to install/update to the current version of Eudora contact Frank Lopez at ICIT. For reason not apparent to me, the ICIT web page offers download links for obsolete versions only. ICIT does offer guides to the current software version on its web site. These guides, however, are simply parts of the official Eudora manual, and not everyone is good at using official software manuals. This advice page assumes that you are already familiar with the basics of Eudora., it is not a Eudora primer for the novice.

I have two questions repeatedly over the last few months -- actually, I have heard the first one for quite some time:

What can I do about spam?
How come that some messages are downloaded/retrieved at home, but at the office (and vice versa)?

Missing messages. Let me start with the second question. Many faculty use Eudora both at home and at the office, and many have Eudora so that all messages are "left on the server" when retrieved from one location (say office) and are automatically deleted when retrieved from the other (say home). In theory, all messages should be available at the "main" location. But several colleagues claim that this does not work 100%. I have not had an opportunity to investigate one of these cases in detail, but my best guess (based on what these colleagues told me) is that they let their Eudora inbox grow too large. It is important to keep the Eudora inbox as small as possible, e.g., by moving incoming messages to other folders. The reason is that the inbox -- in contrast to other folders -- is loaded into memory by default, so a large inbox consumes a lot "system resources" (which is particular relevant if you run an older Windows operating system like Win98/Me), and, as a consequence, Eudora may behave erratically not executing certain tasks properly, certain support files (like a spool file which keeps track of which messages have already been downloaded from a particular server) may get compromised, etc. So, this page addresses the issue of keeping your Eudora inbox small by use of filters.

Spam. I don't want to go into all the details here again, many have been on hunter-l and relevant postings are still available via the web archive for hunter-l. Though I have heard good things about some spam fighting programs/utilities, I am still rather reluctant to let someone else decide which of my mail is spam. I rather do the sorting myself. And this is not enormous chore thanks to the use of filters.

What are "filters"? Filters identify certain classes/groups of e-mail messages for which you specify processing instructions which Eudora then executes automatically as it downloads messages from a server. Examples include:

Someone keeps sending you annoying messages (hate mail). You can set a filter that all message from this sender are automatically thrashed; if you want without that you even see them.
All messages from a specific e-mail discussion group (e.g., hunter-l) are automatically sorted into a folder called "hunter-l"; they do not clutter your Eudora inbox anymore.
All messages from unknown senders are automatically sorted into a folder called "suspicious" (what you call this folder is up to you), which you will check as time permits
All messages sent from top Hunter administrators are sorted into a folder "read immediately" and a sound is played to indicate their arrival

I guess you understand the concept.

How to set filters?
To set/modify filters, go to "Tools"/"Filters". This will bring up the filter window. See screen shot my own filter window (on my home station) as an example below. Of course, if you have never used filters, the list of filters in the box on the left will be empty and you will start by clicking the "New" button beneath the box:

The details for the filter highlighted on the left are shown on the right. In this filter the "group of messages" is defined rather narrowly: that the message is sent from a particular e-mail address. Technically: that the "from:" field "contains" a specific e-mail address.

You can use different parts of the message to set up a "match" and there are many other options on how to compare/match a particular part of the message with what you specify. Most of them are intuitively clear, but some are fairly technical like "matches regexp". I won't go into this here, but via use of "regular expressions" you make your match definition as complex as you want (but you may want to take refresher course in formal logic first).

For people with lesser skills, and you can simply connect two such conditions (pretty much the same way you construct a [Boolean] search a journal article data base).

And here is an example of such a definition ("using Boolean operators"):

In many cases, a simple definition will do. But let us finish the discussion of the first example (going back to the first screen shot). While the upper part of the right side contains the "match", the lower part defines the "action(s)". Note that several actions can be specified. In this example, the first action is to transfer the message immediately to the trash can; the second action is to keep some record of it, here by requested to record its arrival in the filter report. So, you won't get annoyed/disturbed by such a message, but if needs arises you can check whether more messages had been coming in. The third action is to "skip rest", i.e., all the following filters will not be applied to this message -- even if this message should "match" one of the following filters. One important lesson: the order of the filters is important and will affect the disposition of the incoming messages. The filters can easily be reorders by clicking and dragging with your mouse.

Let us take a look at other available actions:

The "Transfer to" action is the most important for the purpose of this discussion, but note that you can also "forward" or "redirect" specific messages automatically. So, you may want to set up a filter for each e-mail discussion/announcement list you are subscribed to and have incoming messages automatically be sorted in matching folder. Your inbox will stay clear and you can get to your "list folders" when time permits.

Let's go to the last filter in my list, the "junk filter":

Any message which has not been transferred yet (like all the e-mail list messages here) and which

does not come from an address contained in my Eudora addressbook ("Eudora Nicknames") and
which does not come from within the CUNY domain

is preliminary classified as "junk" and put in a folder which I chose to call "A-junk" (but you can call it anything you like). Again, this keeps my Eudora inbox small and I can still look at all my mail, quickly scanning the "junk folder" whether there is a non-junk message. The rest gets quickly disposed of, highlight all messages (click first, then Shift-click the last) and transfer to Trash.

Here are a number of things you can do to keep the number of "false junk" classifications at a minimum:

Keep your Eudora addressbook current, e.g., by using the automatic addressbook entry creation feature (with a message open go to "Special"/"Make Addressbook entry ..."), a 2 click affair.
Instruct your students to put your course number (e.g., Soc240) in the subject field if they contact you via e-mail. This way you can easily create a filter and put incoming messages in a class folder, no matter where the student is sending the message from.
Instruct other possible senders (e.g., applicants when doing a search) to put a specific term in the subject field. Again, this enables you to set up an efficient filter.

Filters may seem a bit intimidating at first, and in the beginning you may not always to set a filter exactly the way you envisioned it. But it is really not that hard to learn to use filters, and there is a big payoff.

Good luck.