Thunderbird Spam Control Best Practices

This document is based on Thunderbird v. 1.5.0.2

Potential spam or junk mail messages are flagged in the subject line of each message as POTENTIAL SPAM. This allows CU-Boulder e-mail users to filter spam and junk mail messages away from their inbox. For more information about ITS's effort against spam go to www.colorado.edu/its/email/spam.html

Create A Spam Filter

1. To create a spam filter using Mozilla Thunderbird, click on the Tools drop-down menu and select Message Filters...

2. The Message Filters window will open. From the Filters for: drop-down menu, select your mail account. Click New..., as shown below:

3. In the window that opens, give the filter a name such as Potential Spam.  For the first drop-down menu, select Subject. In the second drop-down menu, select contains, as shown below:

4. In the text box, type POTENTIAL SPAM, as shown below:

5. In the Perform these actions: section, select Move Message to from the first drop-down menu. From the second drop-down menu, select Junk on Local Folders, as shown below:

6. Click OK. 

7. In the Message Filters window, make sure all of the settings are correct and click Run Now if you have Potential Spam messages in your inbox, as shown below:

Identify Senders That Are Not Spammers, Add Them to the Address Book

Identify the senders that are not junk mail senders to ensure that mail from specific users doesn't end up in your junk mail by adding them to your personal address book. To prevent senders in your address book form being tagged as potential spam, follow the instructions below:

1. Click on the Tools drop-down menu and select Junk Mail Controls. 

2. In the window that opens, check the Do not mark messages as junk if the sender is in: checkbox and select Personal Address Book from the drop-down menu, as shown below: 

3. Click OK.

Enable the Thunderbird Built-in Spam Filter

Thunderbird has a built-in filter, which can be adjusted and tuned for your needs. You may need to spend a week or two teaching it what messages are spam and what messages are not.

1. Localize the settings panel for the spam filter by clicking on the Tools drop-down menu and select Junk Mail Controls. (Note: Make sure to select the correct account to change the settings).

2. Make sure the Do not mark messages as junk if the sender is in: is checked and Personal Address Book is selected from the drop-down menu, as shown below:

3. In the Handling section, we recommend that you check mark and select the following options:

• Move incoming messages determined to be junk mail to:
  • "Junk" folder on
  • Then from the drop-down menu, select your account
• When I manually mark messages as Junk:
  • Move them into the "Junk"folder
• When displaying HTML messages marked as junk, sanitize the HTML

4. Then, click on the Adaptive Filter tab, and check mark the Enable adaptive junk mail detection, as shown below:

5. Click OK.

Keep Your Address Book Up-To-Date

1. Ensure you use current (updated) email addresses for recipients. Check the contents of your distribution lists and address books for accuracy.

Keep Thunderbird Up-To-Date

1. Ensure your email client is regularly patched with the latest updates and fixes.

2. Click on the Help drop-down menu and select Check for Updates...

For more information about spam go to www.colorado.edu/its/email/spam.html