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Create a Spam Filter in Webmail

The Zimbra service was retired on December 31, 2015.


You can create a spam filter to automatically filter or delete email that has been labeled as spam by the Stanford spam filters.

The number of "#" signs (pound or number signs) after the word "Spam:" indicates how sure the system is that your email qualifies as spam. By default, all email marked with five # symbols is discarded before it reaches your mailbox. Also, all mail marked with four # symbols is filed into a folder labeled Junk that can be accessed via Webmail or an email program configured for IMAP. Messages more than 30 days old are automatically purged from your Junk folder.

The following instructions show you how to create a spam filter that filters email marked with three or more # symbols into the Junk folder. You can make the filter more sensitive to spam by choosing to filter messages labeled with one or two # symbols.

You can also choose to have messages discarded rather than moved to the Junk folder. However, the Stanford spam filters are not perfect. Legitimate email occasionally gets labeled as spam. Such mail usually gets a "[SPAM:#]" or "[SPAM:##]" tag. If you do choose to discard messages tagged as spam, that email is gone forever and cannot be restored.

Creating a spam filter

  1. If you haven't already done so, go to and log in to your Webmail account.
  2. Click the Preferences tab.
  3. Click the Mail Filters tab and then click New Filter.
  4. Enter the following information in the Add Filter dialog box:
    • Filter Name: Spam Filter (or whatever name you want to call this filter)
    • Active: checked
    • Under "If any of the following conditions are met," select Subject,select contains, and type [SPAM:###
    • Under "Perform the following actions," select File into Folder and then click Browse.
    • In the Choose Folder dialog box, click Junk and then click OK.

      Choose Folder dialog box
    • Do not process additional filters: checked (this prevents additional filters from being applied to a message after the first match so as to avoid contradictory actions)
  5. Click OK to save your spam filter.

    Add Filter dialog box
  6. Filters are applied in the order they appear in the list. If you want the spam filter to run before any other filters you may have, click the filter name and then click Move Up until your spam filter is at the top of the list.

    active filters
Last modified December 9, 2015