Mail Security provides some preconfigured match lists that you can use with content filtering rules and the File Name Rule file filtering rule. You can also create your own match list or modify an existing match list. Match lists support literal strings, DOS wildcard-style expressions, or regular expressions.
To create or edit a match list
In the console on the primary navigation bar, click Policies.
In the sidebar under Content Enforcement, click Match Lists.
Do one of the following:
In the New Match List window, in the Title box, type a name for the match list.
You can only configure the title when you create a new match list.
In the Description box, type a description for the match list.
In the Match Type box, select one of the following:
In the Filter box, type a literal string, regular expression, or DOS wildcard-style expression.
Enter one expression per line. You can link several regular expressions to form a larger one to match certain content in email.
On the toolbar, click Deploy changes to apply your changes.