Mewlan Anti-SPAM resource center

This section describes how to create SPAM filters for three of the most common mail clients.

Create-your-own filters

Most mail clients allow you to define custom Filters that will process your email in a certain way, based on rules that you program into the filter. Filters are based on looking for certain strings in the Headers, subject, or body, or the mail message.

This is the least expensive and safest solution, if implemented properly; but it is only as effective as the amount of effort you are willing to put into it.

Pick your email client and learn how to set up your own Filters: Outlook Express, Eudora, Netscape Communicator.

Outlook Express

OE mail filters are moderately sophisticated. You can scan subject, body, sender, to, but you cannot scan the Full Headers of a message.

This little tutorial works for Outlook Express versions 5 and 6. Look here for Outlook, here for other versions of Outlook Express.

The first step is to set up a SPAM Folder to filter your suspect messages into. Right-click on the Local Folders icon and select New folder. Type in the name SPAM and click OK.

Now, click on the Tools menu, go to Message Rules and select Mail....

The Message rules window lets you process incoming messages according to a set of rules you create. When you have more than one rule, you may Move rules up or down in the list. Rules at the top of the list are used first. This is useful, for example, when you have a positive rule like: when the message is addressed to me, move it to my Inbox. The very next rule would be for messages not addressed to you, and would place them in the SPAM folder.

Be aware that if you are on mailing lists, the messages are usually not addressed directly To: you, rather they are addressed to a group of people, and your address was in the BCC (Blind Carbon Copy) list. Since you do not want to discard the message, you may need to create a positive rule to place them in your Inbox, before the SPAM rule that would place them in the SPAM folder.

Click the New... button. There are a collection of different conditions you can check (see the next illustration).

Eudora

Eudora mail filters are very sophisticated. It is possible to filter based on mail headers, which means that even though that deceitful SPAMmer changes the From address, the actual server that the message came from will be filtered just the same. Eudora versions from 3 on include this feature.

First, create a mailbox to store your SPAM in. Highlight the Eudora folder symbol at the top of the mailbox list, then click on Mailbox, and select New.

Type in the name of your mailbox (SPAM) and click OK.

Click on Tools menu and select Filters. Click the New button. In this case you are only going to filter incoming mail messages, so that is the only option you need to select. You can filter on different characteristics of the message.

The easiest filters are based on the Subject of the message. Select Subject.

Contains is the qualifier we want so there is no need to change it. In the next box to the right type in mortgage rates. We will only use one test for this filter, leave the next drop-down list set to ignore. Skip down to the Action Section, click on the first item and select Transfer To. Click on the button just to the right and select SPAM (or what ever name you gave the folder). When you are done adding filters click on the File menu and Select Save. Then click the File menu again and select Close. There are many options to choose from: the most useful is Any Header.

Viewing the Full Headers of a message tells you what server the message actually came from. To do this, double-click on the message you wish to examine and click on the BLAH BLAH BLAH button above. Look for the HELO command in the header information.

Since the idea is to filter all messages from that server, not just messages that happen to be addressed From: pfzlg@cs.ucl.ac.uk (this address will change often), a filter on All Headers for wangtong.net and eurocontrol.be will be most effective. It is likely that you are getting a lot of SPAM from one or the other of those servers on a regular basis.

There is also a Make Filter function on the Special menu. This function is a much more limited version of the process explained above. It is only useful if you wish to filter a specific sender by email address.

Eudora filters are powerful tools that can help you organize your email. As you develop your own filters, be sure and keep an eye on the list of mailboxes on the Left hand side. They will tell you when there is an unread message placed in one of them (by becoming bold). Until you learn the ropes, we recommend keeping a close eye on unread email, and not using the Delete from server option. A complete tutorial on how to use filters is located at the Eudora web site, for PC or Mac. 

Netscape Communicator

Mail filters in Netscape Communicator are fairly sophisticated. Version 7 of Netscape has a better filtering mechanism than version 4.x but it is not in general release yet. Version 6 did not offer any mail filtering at all.

Open your Netscape Inbox. First create a SPAM mailbox to deposit your filtered messages into. Right-click on the Local Mail folder and select New Folder.

Type in SPAM and click OK.

Click on the Edit menu, select Message Filters.

Click on the New button.

Begin by naming your filter. It is easiest to give it the same name as the word you are filtering on.

It is simplest to filter on the subject of a message that contains one of the key words from the Spam word list. Then Move to folder SPAM.

The More button lets you add conditions, so that you could check on other factors. For example, you could add a condition or the To of the message doesn't contain, and enter your email address.

That way, only messages where the subject contained the word mortgage that were addressed directly to you would show up in your inbox. All others would be sent to SPAM.

The operation of the filters in Communicator 7 is very similar. Netscape 7 also allows you to filter on headers, which is a much more powerful feature. Click on the Tools menu and select Mail Filters.... On the list of filters, there is a Customize entry. Add a new filter for Receive and filter on the actual sending mail server.

In any version of Netscape you can view the SPAM message as usual, click n the View menu, go to Headers, and select All. Look for the HELO command and see what server posted the mail.

wangtong.net and eurocontrol.be are the servers to block here. This will block all email coming from those servers regardless of what the from address says. SPAMmers change the from address all the time in an effort to hide where they are really sending from.