Using the Auto BCC Feature to Copy All or Part of a Mail Stream

Applies to HMS Version: 2.1+
It can sometimes be useful to send copies of some or all messages being delivered through an account to one or more addresses. This functionality may be used for auditing purposes, data retention, message consumption, or many other reasons. The Hurricane MTA Server contains an Auto BCC feature that allows multiple such configurations. Each configuration checks for messages with matching recipients, where the matching can be against specific addresses, domains, or all mail. Currently this feature can only be configured through flat files.
Considerations
The following should be considered before using this feature:

If a single message is addressed to multiple recipients, only a single copy of that message will be Auto BCC'd. The BCC operation is not recursive, so recipients added to BCC by this feature that would also match an address replacement entry would not cause a second or infinite round of addition.

Configuration
This feature is enabled and configured by adding a single line to the [Other] section of the general.config file found in an individual account's config directory. Please remember to reload the target account's configuration after making these changes in order for those changes to take effect.
Field: BccAdd
Description: A ~~ delimited list containing a regular expression a pipe symbol and a comma delimited list of addresses to add when the regular expression matches an existing recipient address. The original address that caused the match will not be removed.
Example: The following example contains two rules in order to show how to configure multiple Auto BCC rules:
BccAdd=@example.com|log@example.org,log@example.com~*~filter@example.com|log@example.com
In the above example, the addresses log@example.com and log@example.org will be BCC'd with any message sent to the @example.com domain. Additionally, log@example.com will be BCC'd with any message sent to the filter@example.com address.
Related Resources
For more information about writing regular expressions, we recommend third-party resources such as the following:

http://www.regular-expressions.info/quickstart.html - An introduction to regular expressions
http://www.regular-expressions.info/reference.html - A quick reference to core regular expression syntax
http://www.regexpal.com/ - An online regular expression tester. Highlights test data that matches a regular expression

The following Knowledge Base articles may also be of interest:

Using the Auto BCC Feature to create One-to-Many Recipient Aliases