Once the Spam Killer service is purchased from your Customer Area->Order section, your domain's MX record will be pointed to a special server configured with a MailFoundry hardware email filter. There all the incoming messages will be scanned for spam and viruses. The viruses will be deleted and the spam messages will be marked.

If a message is marked as spam, the Subject field in the header will be rewritten and the following label will be added: *SPAM*

For example the Subject field will be renamed from:

Subject: My message title

to:

Subject: *SPAM* My message title

Also, more header fields will be added:

X-Spam-Level: *
X-MailFoundry: spam
X-Rule-ID: 4b3727a70027 (1261905831.39)

The above headers identify the message as spam according to a defined rule. The rule ID is shown.

You can set local filters on your e-mail client and move such messages in a defined folder or discard them.

As an example we will explain how to set such a custom filter in Mozilla Thunderbird:

1. Open your Thunderbird e-mail client and navigate to Tools->Message Filters.

2. Click on the New button to add a new filter.

3. Go to the drop-down menu with default value Subject and choose Customize (the last item in the drop-down list).

4. Define a new message header in the new box. You can add "X-MailFoundry" as a header.

5. Then click Add and then OK.

6. From the same drop-down menu choose the new header you have entered ("X-MailFoundry"), then choose "contains" from the second drop down and enter "spam" in the third box.

7. You can run the filter from Tools->Run Filters on Folder