Dealing with spam

(Last updated Dec 13, 2006)

Spam "Spam" not just a tasty meat product. It is also the common name for unwanted email messages, usually advertisements, that show up in your inbox. Many people receive hundreds of spam messages for each legitimate email. Eventually a solution will be found. Until then, these simple steps will cut down on the unwanted email messages that you receive.

Avoid getting spam

  1. Keep your email address private. Never allow your email address to be posted on the Internet. Even if your address is only posted in a GIF file, you will still get spam.
  2. When dealing with online vendors, use a secondary email address instead of your main one. Many vendors will send you spam if you purchase from them, and others will sell your email address to spammers.
  3. Never reply to a spam message. This would only confirm to the spammer that they have reached a live person, and you will receive even more spam. Don't bother reporting spam to the sender, the ISP, or the authorities. It's usually a waste of time. Also, never set your mail reader to reply automatically to incoming mail. This would turn your computer into a beacon for spam.
  4. Do not put your email in any publications, such as books or research papers. You will get spam from equipment vendors, antibody dealers, and the like.
  5. Make sure "read receipts" are turned off. Otherwise, the spammer can tell when you read the spam message. This proves that a live person is reading their spam, and guarantees you will get more. In Outlook, click Options on the Tools menu, click the Receipts tab, and then select the Returning Read Receipts option to turn off receipts. In Pine, type 'sc' to reach the configuration screen.
The best way to eliminate spam is to change your email address and keep it a secret. If no one knows your email address, you will not get any spam.

Blocking spam

The email server at our institute uses Spam Assassin along with some extra plugins to identify spam. The software uses optical character recognition and can even identify those spam messages that consist of nonsensical text accompanied by an advertisement in an attached image. However, by default the software doesn't delete your spam; it only marks the spam messages by adding the word "***SPAM***" to the subject line. You must take one additional step if you want your spam to be deleted automatically. This can be easily done using the following step-by-step procedure.

  1. Telnet to the email server (engram) by typing the following command in a DOS box:
    (Or better yet, use ssh). Use your normal login name and email password.
  2. Create a file called   .procmailrc by typing
     pico .procmailrc 
  3. Paste the following text into the .procmailrc file:
       * ^X-Spam-Status: Yes
    (the character between two colons is the number zero).
  4. Hit Ctrl-X to save the file.
  5. Now, any message that Spam Assassin marks as spam will automatically be saved in a special folder called "spam". You should check this file occasionally in case a message gets misclassified. This is a lot easier to do if your email client is set to use IMAP instead of POP3.

Changing your spam sensitivity setting

If some spam is still getting through, or if real messages are being classified as spam, change your spam sensitivity setting as follows:

  1. Telnet to the email server (engram).
  2. type cd   .spamassassin and press Enter.
  3. Edit your user preferences file by typing pico user_prefs
  4. Move the cursor to the line that says "required_hits" and change the number to something else. A higher number will allow more messages through, while a lower number will classify more messages as spam.
  5. Press Ctrl-X when finished. Your preferences have now been changed.

Blocking specific types of spam

Some types of spam can't be identified by Spam Assassin. Often this spam can be blocked using special procmail rules. We have a large collection of such rules. If you're still getting spam after taking all the above steps, let us know and we will change your account so that these rules also apply automatically to you. Or just copy this .procmailrc script into your home directory. (You may have to edit it first).

If that doesn't work

Some spammers constantly change their "From" address. For example, a company called "Superarray" ( sends us a lot of spam, using a variety of different senders. If you receive a lot of spam from one particular domain, let me know and I'll add them to our firewall. This is an extreme method, since no one at the institute will ever be able to deal with that company again.

If you have trouble

If you can't do these steps successfully, feel free to ask us to do it for you. But please try it yourself first.

For more information about configuring your .procmailrc file, click here.