Spam filtering on the cheap for your domain's email

MX Guarddog is a great, free service for protecting your email from spam.

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A little over a year ago I was faced with a spam filtering problem, but it’s not what you might expect.

I had been using the paid Postini service for filtering spam sent through my domain, when Google acquired Postini and, once acquired, killed it off and forced users to transition to their Google Apps platform. I found the Google Apps interface to be clunky and, worse, my users found it difficult to use. In addition, I had no interest in sending all the mail for my private domain through Google’s servers. Suddenly the bang I was getting for my Postini buck had lost its pop, so I went looking for an another solution.

There are plenty of apps you can install on your Mac to filter spam, but, as is the case with virus scanning on PCs, most desktop software solutions are playing a game of catchup that requires training time and constant updates, which is why I was looking for a web-based solution.

There are also numerous web-based options for spam filtering, but they tend to be aimed at and priced for corporate customers. For example, a year’s worth of McAfee’s SaaS mail filtering is about $14 per user, Google Apps costs about $25 per user per year, and most any other service you’ll find will run somewhere in that range. So, imagine my somewhat cynical surprise when I came across a solution that was free: MX Guarddog.

Oh, I see the way you’re looking at me... because that’s exactly how I was looking at myself. For several days. Wondering what the catch was.

Funny thing is... there was no catch. MX Guarddog is great spam filtering that you can get for free simply by putting a link to MX Guarddog on your homepage. (There’s no time here to explain the “whys” of free MX Guarddog, but if you’re interested, check out Who is MX Guarddog to learn why they made it free.) And, if you don’t like the idea of linking to MX Guarddog’s homepage, you can pay 25 cents per user per month.

The setup for MX Guarddog is easy, but it’s important to note that in order to use the service you must have email that is hosted using your own domain. No Gmail. No AOL. No Yahoo. No other addresses hosted on those types of public domains.

The addresses being filtered must be something like:

Here’s how to set the service up:

  1. Go to MX and click the Register link.
  2. Provide your name, email address, and the domain you want to protect. (It’s best here to provide a mail administrator address and contact info.)
  3. Look for MX Guarddog’s activation email and click the activation link.
  4. Login using the account information provided in the Postmaster email you receive after activation.
  5. Add a link to your website.
  6. Add the email address you want protected by MX Guarddog.
  7. Provide MX Guarddog information about your email servers.
  8. Update your MX records to direct your email through MX Guarddog’s servers.

When you log in with your email address and the MX Guarddog-provided password you’ll see the MX Guarddog Domain Dashboard. It’s here you can add email addresses, create the web-link required for free filtering, add your email servers, and get info on how to update your MX record.


MX Guarddog Domain Dashboard

To generate a web link:

  1. From the Domain Dashboard, click Earn Tokens. (There’s a “Buy tokens” link if you’d prefer to pay.)
  2. Add the URL for the domain you want protected.
  3. Copy the link code and add it to your website.

MX Guarddog offers several options for adding the email addresses you want protected, including adding them manually, importing them in bulk, and LDAP or cPanel synchronization. What makes the most sense for you depends on your setup and needs, but MXGuardog’s site provides clear documentation on how to use each of these options.

To tell MX Guarddog where to send filtered mail:

  1. Click the link to Define your email servers.
  2. Enter your domain name or the IP address for your mail server.
  3. Enter a port number, if it differs from port 25.

Updating your MX record information will vary depending on who hosts your site and how your DNS information is set up. Click the Update your MX records link in the Domain Dashboard and follow the instructions that make the most sense for your specific situation.

Once you’ve completed these steps MX Guarddog will begin filtering your email and sending each of your users a quarantine list. For your users to log in and manage their list have them:


MX Guarddog quarantine list

  1. Click the login button at
  2. Click the “Need a password” link.
  3. Enter their email address.

They will be sent a link for resetting their password and enabling their login.

So simple and some of the best spam filtering you’ll find at any price.


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