How to block spam and prevent spam email from reaching your Inbox by washing your email

AKA: “How to Create a Sewage Treatment Facility for Spam”

If you’ve been online any length of time, you probably have an email address or addresses that are receiving spam (bulk, unsolicited, commercial email). This article will outline an inexpensive way to keep spam out of your Inbox (or at least significantly minimize the flow from what it is now). The article is written primarily for internet/email users who receive email through a hosting provider on their own domain name or domains and for those who do not currently own their own domain but are open to the idea and would like to significantly reduce spam in their Inbox.

[Updated 13 OCT 07: A few folks have reached out to me about setting this up for them. I've made it as clear as I can here. If it still does not make sense I will be happy to set this up for you for $50 USD (my time) plus actual costs. Contact me at (503) 946-6450 if interested. -AB]

[Updated 6 OCT 07: In testing this strategy I purposely re-activated one of my old email addresses that is about 10 years old and was getting over 100 spam messages per day when I shut it down. In the past two weeks I've gotten zero spam on it, so I know this really works well. Besides, it's really not necessary to use challenge/response services like SpamArrest that force those who write to you to type in "pretty dog" into a box or look at an image of a squirrel and type in "squirrel" just to prove that they are human. It's actually quite silly when you think about it.]

Executive Summary for Advanced Users

If you are a technical person, you will understand this paragraph and may not need to read further. I’ve added this section to save you time. Basically what I’ve done is to set up a couple of POP accounts on one of my domains, a public one for inbound email and a private one for two-way communications. I have an account at pobox.com and am using their extensive server-side spam filtering to wash inbound email. It is surprisingly robust and allows you to wash mail against all the major SBLs and even block by country of origin.

I use aliases as email addresses and forward inbound mail to the pobox.com account where the washing takes place, then forward it back to my POP accounts as clean email. I check the POPs using IMAP from my iPhone or desktop email client and I get virtually zero spam so I know it works - even on aliases that have been compromised several years ago that used to dump over 100 spam messages/day in my Inbox. Never again.

There. That’s the Cliff Notes version. If the above was Greek to you, read the rest of the article below.

If you do not own your own domain name

[Users who already own a domain and hosting account should skip this portion and read on...]

A domain name is a .com/.net/.org/.info etc. name that you have purchased and is normally mapped or directed to a web hosting account. There are numerous advantages to owning at least one domain name and receiving your email on your own web hosting account as opposed to one of the free services such as Gmail, Yahoo or paying for AOL.

A primary advantage is that as a user you have considerably more control over how your email is received and what you can do to filter it. The cost of owning your own domain name and hosting account is quite minimal, even if you simply wanted to test it for a month or two, and is definitely worth both your time and money. You can get a hosting account for as little as $10-$30/month and buy a sparkling new domain name for around $9.95/year. All told, if you wanted to test the strategy I am outlining here you could do so for a modest investment of between $20 and $40, a very inexpensive sum considering that it may indeed completely solve your spam problem.

Getting a hosting account

For inexpensive hosting, I recommend either Pair Networks or Dreamhost. Both have basic hosting plans that can be purchased and set up within 24 hours. Many plans also include a free domain name registration, thus eliminating the registration fee outlined below. However I still recommend registering your domain via the link below because if you decide to move hosting accounts it is much easier to do so if your registration is not with your hosting provider. You’ll feel quite foolish if you want to move to a new host down the road and you have to get the current hosting provider’s permission to do so because they are also the registrar for your domain.

A web hosting account will give you a certain amount of space to put up web content if you choose to do a web site, but most importantly it will allow you to create POP accounts (mailboxes) and aliases (email forwarders). For the purposes of explanation in this article I will assume the domain you use is SOMEDOMAIN.COM.

Registering a Domain Name

For domain registration, I recommend GoDaddy.com, however there are other domain registrars. Use the search box to find one you like, register it and during the registration process you’ll need to set up custom nameserver entries that direct to your new hosting account. It’s probably a good idea to get a hosting account first so you know which nameserver settings to enter when you register your domain name, but you can also go back and change these entries later on if you wish.

Once you have a hosting account and domain name set up, read on.

If you already own your own domain name and hosting account

In a previous article I described how you can easily create a robust and highly searchable archive of your email. Chances are, if you’re reading this you probably already have a few aliases (email forwarders) and POP accounts (mailboxes) set up. If not, you should be familiar with how to create these on your hosting account and what the difference is.

An email alias simply reroutes/forwards inbound email to another address or mailbox. An example of this is if you had two email addresses, brad@somedomain.com and steve@somedomain.com both forwarding email to a mailbox (POP) called emailbox@somedomain.com. Any email sent to either of the former email addresses would route to the box, which you would then check via your desktop email program and download messages to your computer.

An Overview of Mail-Washing

This strategy involves creating one or more email aliases, forwarding them to a robust, server-side spam filtering service and then forwarding the mail from there back to a POP box on your hosting account. I call this process “Mail-Washing”. You can call it whatever you like. A good analogy - and perhaps a very appropriate one considering the nature of spam and spammers - is to look at this like a sewage treatment facility. You’re routing all your mail, crap and all, to a place that will look for and remove the shit, cleansing your mail before delivering a clean product back to you.

It’s important to realize that no spam filter or filtering process is 100% accurate. What I am about to show you will allow you to set your own server-side spam filters to be very lenient or extremely aggressive, as you wish. You’ll need to experiment with the settings to determine what works best for you.

Step 1: Sign up for a POBox.com account

POBox.com is an email forwarding service that receives email and forwards it. In the process the service also makes available to its users a very robust set of server-side spam filters not found anywhere else. For example, I can control inbound email so I only receive email from senders who originate in the United States, blocking all other countries. Or, I can receive email only originating in Canada and the U.S. Or, I can “scrub” my email against several ISP blacklists of known spammers, rejecting the mail, deleting it before it reaches me or simply tagging it as spam so my desktop email program routes it to the junk folder.

POBox.com offers a free 30-day trial, which will give you ample time to test out this strategy without investing further dollars. After the trial, if you wish to continue with the service, it is only a very affordable $20/year.

Click here to sign up for a test drive now. Suggested account name is “Firstname.Lastname@pobox.com”, but you can choose whatever you wish.

Step 2: Setting up the Sewage Treatment Facility

Any email address you use or give to others should be an alias, that is, a forwarding address rather than an actual mailbox address. For the purposes of this example, I’ll say that we’re setting up a Mail Wash for Barbara Smith.

Barbara has a couple of email addresses that she uses and a couple of mailboxes:

bs@somedomain.com >> forwards to >> private@somedomain.com

Barbara uses this only for two-way “real” email communication, not newsletters, not discussion lists, not software registrations. It is her private email address.

Logging into her pobox.com account (barbara.smith@pobox.com), she clicks on Services and then Edit Addresses and Forwarding.

She routes all email received by barbara.smith@pobox.com to private@somedomain.com.

Then she goes into her hosting provider and changes the email alias bs@somedomain.com so that it forwards to barbara.smith@pobox.com.

Next she goes back into her pobox.com account and turns on the spam filtering, clicking on Services then Edit Spam Protection. Here she explores the options and chooses standard settings or aggressive; or customizes the filters she wants to use.

Now all of Barbara’s private email is received at bs@somedomain.com, then is forwarded through a Mail-Wash account at pobox.com where spam is blocked, rejected, tagged or filtered, then the clean mail is forwarded again to her mailbox (private@somedomain.com).

One sewage treatment facility created, one to go.

Barbara’s second address that she uses is for newsletters, discussion lists, etc. and it’s an email alias called “barbara.smith@somedomain.com”. This alias forwards/maps to a second mailbox called “public@somedomain.com”.

The pobox.com account allows for the creation of more than one forwarding address. Since barbara.smith@pobox.com already forwards to her private mailbox, she needs to create a new one that will forward mail to her public mailbox. So in pobox.com she clicks on Services > Edit addresses and forwarding > Create a new group. And she creates “barbara.smith2@pobox.com” and sets it to forward to “public@somedomain.com” (her public mailbox).

Next she goes into her hosting provider account and creates or modifies the alias “barbara.smith@somedomain.com” and sets it to forward to “barbara.smith2@pobox.com”. Spam settings are already set, so no need to change.

A Visual Summary

Here is a visual summary of what was created:

bs@somedomain.com (private alias)

barbara.smith@somedomain.com (public alias)

Testing

Next she goes into Outlook, Entourage, Eudora, Thunderbird, Mail or whatever email client she uses, and she adds two new POP accounts (or IMAP as you prefer), sends herself a couple of test messages to each alias she set up and then checks/downloads email from the following mailboxes:

private@somedomain.com

public@somedomain.com

Being Mobile

And, because she does not like to be tied down to one place, Barbara tends to like to pop into any computer terminal and check her email via a Gmail account, barbara.smith@gmail.com.

To receive copies of “clean” email via her Gmail account, she logs into her pobox.com account and modifies the pointer addresses that email is forward to. She simply adds a comma and then adds her Gmail address so in addition to forwarding clean email to her POP accounts, a copy of all inbound mail is also forwarded to her Gmail account that she can check from Brazil or Hungary or wherever.

She also read my other article on how to set up an off-site, searchable archive of email, located here.

Summary

I’ve been testing this strategy for a month now, using ten-year old email addresses that normally received over 100 spam messages per day and I get zero spam on these addresses. It works extremely well for me.

I hope you find this useful!

FAQ - Frequently Asked Questions

Q: “Why couldn’t I just forward my email to Gmail and use their spam filtering?”

A: You could, yes. But while the spam filtering with Gmail is quite robust, it is not customizable, meaning that you cannot block by country or turn on and off specific ISP blacklists. The method I describe is far more flexible in terms of options.

Feedback/Questions/Additions/Corrections?

Reach the author at adam (at) adamboettiger.com or provide your feedback by voicemail at (503) 946-6450.

Was this valuable to you? Send a donation to the author to let them know!


Suggested amounts:

October 5, 2007 | Filed Under Email 

Comments

Leave a Reply

You must be logged in to post a comment.