Spam Filter

Spam is a term used to describe unsolicited email which tries to sell you something. Spam can range from annoying adds and get-rich-quick schemes to extremely offensive material.

The Spam Filter tab is used to configure how Lydia will handle spam.

Lydia's Spam Filters are designed to be aggressive. When Lydia detects spam it will handle the spam without notifying you. In this way Lydia differs from other programs that detect spam then ask you what to do with it. When Lydia detects that an incoming email is spam it will either Trap or Delete the email message based on the Spam Filter settings.

Since spam detection is not 100% perfect, it is recommended that you always trap spam rather than delete it. This allows you to view and recovery messages that are incorrectly identified as spam.

Enable Spam Filtering
Check this option enable the Spam Filtering.

Filter when viewing messages
By default Lydia will only filter spam when checking for new email. When this option is enabled Lydia will also filter spam when you choose to view email messages. If you have a slow connection you may want to disable this feature.

Always allow email from Address Book
When this option is enabled email received from an email address in your Address Book will never be considered spam.

Realtime Blocking List
The Realtime Blocking Lists (RBL) are Internet servers that maintain information on known or suspected email servers that send spam. When this option is enabled Lydia will check incoming email against an RBL server to see if the email should be considered spam.

Enable RBL Filtering
Check this option to enable RBL Checking

Servers
This field contains the RBL Servers Lydia should use to check incoming email. You can enter multiple servers by separating them with a comma. The default RBL Server, bl.spamcop.net, provides very aggressive spam detection but may detect legitimate email as spam. If you wish to use a less aggressive RBL Server you can find a list of servers on the RBL Server List web page.

Action
Select whether to Trap or Delete email messages that are detected as spam by the RBL server.

Custom Filters
Custom filters allow you to create your own rules for detecting spam. Incoming email messages are matched against the filters before they are checked against the RBL servers.

You can also create custom filters that will permit email message that might otherwise be considered spam.

The filters are processed from the top of the list down. If an email message matches a filter the remaining filters and RBL checks for the message are skipped. Filters that allow email should always appear before filters that trap or delete email. You can rearrange the filters by using the Up and Down buttons or by dragging an a filter to a new location.

Use the Add and Edit buttons to create or modify a filter.

Custom Filter Properties

The filter properties allow you to define the criteria for the filter.

Click on each of the four fields in the above image for a description of the field.

Header Matching
In addition to matching against common email headers such as To, From and Subject you can also match against other headers.

To match against other headers select If Header then enter the header and text to match separated by a colon (:). For example, if you want to trap email messages in which the X-Mailer header is set to SpamMailer you would enter X-Mailer:SpamMailer as the text to search for.

You can also use If Header to trap email messages in which a specific header is found, regardless of the content of the header. For example if you want to trap email messages that contain the header Apparently-To you would enter Apparently-To as the text to search for.

Regular Expression
Lydia includes advanced filtering through the use of regular expressions. When using a Regular Expression filter a Test RegEx button will be visible. Clicking this button will let you test your regular expression.