SpamAssassin

Official SpamAssassin logo

SpamAssassin is a piece of free, open source software that Gustavus uses on its e-mail server to help identify and remove spam.

Once enabled, SpamAssassin assigns each e-mail a Spam score between 0 and 10 based on certain key words and characteristics of the e-mail. The higher the score, the more likely it is that the e-mail is spam.

Contents

Configuring SpamAssassin

Most of SpamAssassin's features can be accessed from the Spam Filtering Settings page.

Enabling

You must enable SpamAssassin on the Spam Filtering Settings page before it will start marking and filtering spam from your ham (wanted e-mail).

Spam threshold

By default, the Spam threshold is set to 6, but if you find that too much spam is slipping by unmarked, you can lower this. However, if you set the threshold too low, legitimate e-mails might occasionally be marked as spam.

Think of the threshold as tolerance. The lower the number, the lower the tolerance you're permitting for unwanted email. The higher the number, the higher the tolerance. You'll need to strike a balance between the two extremes to allow legitimate email through, yet block unwanted messages. If you train SpamAssassin (see below), your score can be safely set between 4 and 6. If you do not, leaving your score at the default 6 is probably best.

Marking and moving

After enabling SpamAssassin, the phrase "*****SPAM*****" will be prepended to the subject line of all your suspected spams. If you'd like, you can also choose to have all of these suspected spam moved to a special mailbox folder called Filtered_by_GAC, to reduce clutter in your inbox.

Block / Allow lists

Your Block List and Allow List let you specify e-mail addresses you wish to always flag as spam or not spam, respectively. You can also add an entire domain of e-mail addresses using wild cards, such as *@some-spam-website.com.

It's important to keep in mind that due to the open nature of e-mail, you can't necessarily trust these sorts of lists the way you might think they'd work. Spammers often times modify e-mail headers to make it seem as though their messages come from a different address than they really do.

And although it might seem logical to add *@gac.edu and *@gustavus.edu to your allow list, you should not do this. Because of the way e-mail aliases are processed, you'll end up allowing spam sent to e-mail lists to enter your inbox.

Training (advanced)

If you find that after you enable SpamAssassin, your e-mail is being marked incorrectly, either as spam or ham, you can help train SpamAssassin to correctly identify bad email.

If you have an email in your inbox that's spam, just move it to your Filtered_by_me mailbox. SpamAssassin will look through this mailbox every night and use the messages in it to learn what you think spam is. This mailbox should be used in conjunction with your spam threshold (explained above).

External link

Contact us

Please contact the Technology Helpline at 507-933-6111, stop by the Technology Services department in Olin Hall or complete our contact form.