SPAM filtering - Get rid of ad emails

Filtering on your PC

To insure the smallest possible error rate we cannot set a very aggressive setting on our scanners on the servers. However some correct mails may accidently get marked as SPAM, and if you have set the server to disregard spam, then it is lost forever.

Therefor we recommend to use a local filter in your email program to move SPAM marked emails into a folder. That way you can store emails accidently marked as spam, and quickly find them should it be needed.

If you would like to have an extra filtering/scanning that is adapted for your needs and email patterns, we recommend using SAproxy. This is an open source program so it is free.

Filtering on the server

When an email is received by our servers it is analysed via international databases, to see if could be a SPAM email – that is an unwanted ad.

When an email is detected as being SPAM, a label (’SPAM: ’) is added to the start of the subject line and a spam flag in the header is set to YES.

This enables you to filter on this characteristic directly on the server or in your email program.

  1. Start the webmail by going to mail.your-domain.com (where your-domain.com is replaced by your actual domain).
  2. Login as the user (your email address) that you want to set up the filters for.
  3. Choose 'Filters' in the menu in the upper menu.
  4. Click the button 'Add a New Rule' to add a new filter.
  5. Select 'Header'-'X-Spam-Flag'-'contains' in the first line og selects.
  6. Write: 'YES' in the last field. Make sure it is in capital letters.

  7. - If you wish to create a new folder and save them in this on the server, you should choose the option 'Move message into' and write the name of the new folder in the box on the right. This is generally not recommended unless you connect to the server using IMAP, since it requires you to log into the webmail and empty the folder manually. Otherwise you will fill up your mailbox and run out of diskspace.

    - If you want to delete the SPAM emails directly on the server, then mark the option by 'Discard Silently' in the 'Action' area.

  8. In the area 'Additional Actions' mark the checkbox by the 'STOP' text.
  9. Click on the button 'Apply Changes' to activate the new filter.

     

Please notice that SPAM emails that are forwarded from other email address’s (could be an alias or simply another account) will rarely be detected as SPAM and would therefore not be labelled as such.


Category: Postfix server