SpamSieve 2.4.3, by Michael Tsai
Posted: 21-Oct-2006

4 1/2 out of 5 Mice

Vendor: Michael Tsai Type: SHAREWARE

Reviewer: Kevin Zittle Class: UTILITY
$25   Download

Are you tired of SPAM? Well, there is an application to stop it all. It's SpamSieve from C-Command. SpamSieve is a plug-in SPAM filter for popular Mac OS X mail applications. Instead of just marking what it thinks is junk based on pre-set variables, it uses a technique known as Bayesian filtering to learn with your mail and continually improve its understanding of what is and is not SPAM. Simply put, this junk filter is smart, and great for anybody who is tired of SPAM - who isn't?


SpamSieve is Universal and runs on Mac OS 10.2 and above though at least 10.3.5 is recommended. The only other requirement is that you use one of the following supported mail programs:

  • Apple's Mail,
  • Emailer,
  • Entourage (v.X through 11.x (2004),
  • Eudora 5.2 or later (Sponsored or Paid),
  • GyzaMail,
  • Mailsmith (Bundled with Mailsmith 2.1),
  • Outlook Express 5,
  • Powermail.

Once downloaded, you can simply drag the application into the Application folder on your computer. Launch SpamSieve to install the correct script for your mail program. Afterwards, you must set up your mail program to recognize the script and send all incoming mail through the script to test it for SPAM. Precise directions for all of the supported mail programs can be found on the website or here. Since Apple's Mail is standard on all Macs running OS X, I will go through the steps for that program.

First, launch SpamSieve and under its menu, choose to install Mail's plug-in. Then, launch Mail. Create a new mailbox called "SPAM" - make sure it is named SPAM and not Junk or anything else, otherwise SpamSieve will not work. Now, go to Mail's preferences and create a new rule. (The description of the rule must start with SpamSieve, but you can add additional text after that, if you want.) Change the From menu to say Every Message. Then, next to Move Message, select your new SPAM mailbox. Click ok, and, if asked, choose not to apply the rule to your open mailboxes. In summary, make sure the rule looks like this:

SpamSieve Rule

Now, because SpamSieve uses Bayesian filtering, you must show the program what is SPAM and what isn't. The company suggests that, rather than training SpamSieve with all of your mail, you use 65% SPAM and the rest good mail. This proportion allows SpamSieve to make the best progress in improving its filtering. To train messages as SPAM or good, simply select one or more messages and then select one of the newly added options "SpamSieve - Train as SPAM" or "SpamSieve - Train as Good" respectively from the Mail Message menu; there are also keyboard shortcuts for these commands. To tell how many messages you have marked as each, go into the SpamSieve application and choose to see statistics, or keyboard shortcut Command-2. Half way down the window, you can see the percentages, as shown below

SpamSieve Statistics

So in review, you set up your rule to send all incoming mail through the SPAM filter. Then, train the filter with your own mail using the menu commands. Once you have about a 65/35 ratio of SPAM to good, you are all set up.

In Use
Now that your filter has been set up, the in-use part is easy: send and receive mail and never worry about dealing with SPAM again. If one of those sneaky SPAM messages does get past the Bayesian filter, all you have to do is click on the message and "Train as SPAM". SpamSieve will learn what makes it SPAM and then move it into the SPAM mailbox. This also goes for the other way around. From time to time, look in the SPAM mailbox to check for good messages and delete all of the SPAM. If a good message accidentally got marked as SPAM, simply select it and "Train as Good". SpamSieve will learn what makes it a good message and move it into your inbox.

I have used SpamSieve for about a month now. One of its cool features is the ability to see how well the filter is doing via the Statistics window. There is nothing better than seeing that the SPAM filter is actually catching SPAM. Remember, we used this window to see how we trained the program for initial setup? In SpamSieve, simply go up to Filter>Show Statistics or command-2 to see the window, shown below:

SpamSieve Filter Results

Here you can see how many messages SpamSieve has filtered and your daily amount of SPAM messages in the first section. The second section shows how well it has done, listing its false positives (how many good messages it marked SPAM,) its false negatives (how many SPAM messages it marked good) and what percent of messages it correctly marks. It also shows how many messages you have used for training, both good and bad, as well as how many words are being used to identify SPAM messages. The next section shows how many e-mail addresses it blocks and how many it always marks good. The final section shows you the date statistics are being shown from; you can configure the date to see just the past day or week, or the entire time you have had the program. For the month I have used the program I have had, according to SpamSieve's stats, a 95.3% correct percentage. This has saved me much time in reading e-mails, allowing me to get more work done.

I encountered one problem; after setting up the program, I got a SPAM message that was marked good. However, when I tried to mark it as SPAM, SpamSieve wouldn't let me. The C-command website had some suggestions for information to send in e-mail when asking for help, such as the log and screenshots of my set-up. I contacted the author, Michael Tsai, who quickly got back to me on some steps to take, like restarting the mail application. He also sent me a script along with some instructions. After following the directions, I e-mailed the results back to Mr. Tsai who then explained what had been done and what it meant. Although we are not sure why, the problem was fixed by running the script and restarting my mail application. Overall, the customer service experience was great, he was very prompt in his responses as well as very kind and informative, and the problem was fixed. Other then that, I have not had any problems.

As far as preferences go, there is as much customization as you could want, including everything from how hard SpamSieve is on messages to your dock icon. Under SpamSieve's preferences, there are 4 tabs:

  1. Filters,
  2. Notification,
  3. Training,
  4. Advanced.

Under the Filters tab, you have the option to include and not include certain filters such as using Address Book's entries, using the Habeas safe list (a pre-set list of safe addresses) and enabling or disabling SpamSieve's main Bayesian classifier.

Under the Notification tab, you can set notifcations for the arrival of new good mail such as playing a sound and bouncing the dock icon. You can also configure Growl, a free third-party utility which gives you popup notifications of SpamSieve's activities.

Next, under Training, there are options such as whether or not to allow duplicates in the database and training different filters such as the white list and block list or the Bayesian filter.

Finally, under the Advanced tab, you can set how hard you want SpamSieve to be on messages - I left it in the middle as suggested - as well as options like using a photo realistic dock icon or quitting SpamSieve when your mail application quits. No matter how you like your SPAM, SpamSieve can handle it.

SpamSieve Advanced Preferences

Now, I know that I went kind of fast over that stuff, but don't worry, because one of the best features of this application is its manual. The manual for SpamSieve covers everything in the application in great detail, and if there are any questions, Michael Tsai is very easy to contact for help with anything you need!

SpamSieve is a SPAM filter using Bayesian filter techniques, allowing it to learn and grow with your e-mail messages. Its set-up is a little complex, but the accompanied manual walks through the process step by step with lots of pictures. After set-up, you can sit back and not worry about SPAM again. This is definitely a very useful application. It has saved me much time and effort in filtering my e-mail. Anybody who is tired of dealing with SPAM needs SpamSieve; it is smart, easy, reliable and a great piece of software to have.


  • Easy to use
  • Learns with your mail
  • Very reliable after set-up
  • Easy to see statistics
  • Great documentation and support


  • A bit complex to set up
  • Did have one problem (eventually solved)

Overall Rating

4 1/2 out of 5 Mice