Sift through spam with filters' help


Last week, in SpamFighting 101, we talked about keeping out of the sights of the junk e-mailers who turn our Inboxes into billboards for porn sites and phony-diploma mills. This week, in SF 102, we'll talk about dealing with the garbage that pours down the mail pipe despite your best efforts to avoid it.

First, consider that there are two kinds of junk mail. The first comes from a legitimate merchant or Web site that got your name as part of a transaction you were involved in.

For example, you may have purchased a CD online, registered software or done something else to put yourself in the line of fire. Or, the sender may have gotten your name from someone you did business with, particularly if you checked off (or didn't bother to uncheck) a little box that authorized it. In fact, you may not consider all of this e-mail to be junk. If you bought shirts from Eddie Bauer online a few months ago, you may want to be notified of sales -- just not five or six times a week.

These are usually stand-up businesses. They have real addresses, phone numbers and well-tended Web sites. Their e-mail may have instructions or even click-on links that allow you to remove your name from the mailing list. Although the companies don't always pay attention when you do try to opt out, it's usually worth a shot (but read on before you try this).

Real spam comes from bulk mailers who send out tens of thousands of solicitations to any e-mail address they can find. These are the pitches for porn sites, get-rich-quick schemes and other come-ons. You can usually identify these messages because they have a return address that looks something like ""

These, too, often have a click-on link that offers to remove you from the mailing list. Don't take the bait; all this does is tell the spammer that you're a real target, and you'll be spammed again and again. If you're unsure about the legitimacy of the sender, ignore the opt-out link and try the filtering approach.

Filtering uses your software (or your Internet service provider's) to separate digital wheat from chaff, based on information in the message itself. Just how this works depends on your ISP and the software you're running.

More people get their e-mail through America Online than any other provider. Although AOL's proprietary e-mail system is atrocious, the company has made a good faith effort to block spam systemwide before it gets to users' mailboxes. A year ago it wouldn't have been unusual to log on after an absence of a week or two and find more than 100 pieces of spam in my AOL mailbox. Now I rarely find more than 15 to 20.

This is fortunate, because AOL doesn't provide users with much filtering power. On the upside, you can set up the software to allow mail only from particular users, or to block mail from particular users or even domains, such as That's a good way to get rid of repeat junk mail from traceable companies that won't honor requests to be stricken from their mailing lists.

But there's no way to block or route mail based on its content or subject line, or for that matter to channel messages into different folders by category (a useful tool for sorting messages regardless of spam). To set up AOL filters, click on the Mail Center icon on the menu bar, then choose Mail Controls from the box that drops down.

Web-based e-mail services are a mixed bag. Some make an attempt to filter what they call "bulk mail" and put it into a separate folder under your account. Some let you set up your own filters. Possibly feeling pangs of guilt because its system is hijacked so frequently by spammers, Microsoft recently added excellent spam filters to its Hotmail system.

For those using traditional e-mail accounts, Microsoft's Outlook Express and Netscape Messenger -- the two most popular e-mail clients -- have good filtering capabilities. Unfortunately, Microsoft hides its filters under the title of Message Rules, which are available from Outlook's Tools menu. Netscape calls a filter a filter -- you'll find it under Messenger's Edit menu.

Both programs allow you to delete mail or channel it to a specific folder based on its sender, the system that sent the mail, the subject line, text in the body of the message and other criteria. While Netscape's filter system is more intuitive, Microsoft's is more flexible, allowing multiple criteria in a single rule. In addition to dealing with spam, filters can help organize your mail. For example, you can create a Family folder and have all mail from specific family members automatically routed to it, create a HotRocket folder for messages from the boss, or set up separate folders for messages from any mailing lists you may have joined.

Filters can deal with junk mail in different ways. The first question to ask is whether you want to block unsolicited ads altogether or just divert them to a folder so they won't clog up your Inbox. If you decide on the former, you can set up your filter to delete the mail when it comes in; otherwise you can divert it to a specific folder so it won't clog up your Inbox. You can then browse through it and get rid of it at your leisure. I prefer this method and set up a JunkMail folder to catch the stuff.

Creating the right filters is a cat-and-mouse game. Assuming you've already tried unsuccessfully to opt out of their mailing lists, messages from legitimate merchants usually have a valid originating address, so it's easy to set up the trap -- just create a filter that dumps all traffic from that sender to a JunkMail folder.

This will become easier if the industry adopts a proposal to tag the subject line of unsolicited ads with the prefix "ADV:". Although this makes it easy for users to dispatch junk mail, ISPs don't like it because it legitimizes what they see as an unwarranted use of their mail servers.

But even that won't stop real spammers, who falsify the e-mail header information that normally leaves a trail back to the source. This obfuscation includes the sender's name and often the name of the system, or domain, that originated the message. If you're getting spam from different users at, you can create a filter that diverts anything from that domain to the junk pile. But often, even the domain is faked or created by a random name generator. You'll rarely see the same system twice.

Here's where your creativity comes in. As you examine your junk mail, you'll notice that certain words or characters crop up frequently in the subject lines: "$$$" in ads for work-at-home schemes, "XXX" or "Babes" in porn site ads, or "!!!" in all kinds of spam. Filters can search for these, too. They can also search the entire text of your messages, although this can slow things down while you're downloading your mail.

These techniques aren't perfect -- and they don't do anything about the underlying problem -- but if you spend a little time with filters, you can keep your Inbox a lot cleaner and sweep most of the junk out of your life.

If you're really interested in stopping spammers, and you're willing to invest the effort and perhaps a few dollars, check out SpamCop (, a Web site created by a Seattle computer consultant that can track down junk mail originators, complain to their Internet service providers, and provide heavy-duty filtering ($12.50 a year for average users). Even if you don't sign up, you'll find plenty of understandable advice and information here.

Copyright © 2019, The Baltimore Sun, a Baltimore Sun Media Group publication | Place an Ad