Subscriber Pro builds on the already powerful Subscriber to provide an even easier to use script with many advanced features you won't find in many other mailing list scripts. Subscriber Pro includes support for an unlimited number of lists, seperate per-list authentication, Sendmail and Blat mailer support, bounced address filtering, timeout prevention, an optional SQL database backend, a powerful plugin interface, and so much more.
Subscriber Pro previously cost $100, but as of October 2006, it is now free. Donations are welcome. :)
In addition to all of the features of NP Subscriber, you also get all of the following with NP Subscriber PRO (not a complete list of all features):
* Unlimited # of Lists: Create and manage all the lists that you want from the same script!
* Two Levels of Administration: Each list has its own login. Futhermore, there is an overall admin password that is used to configure the script. This administrator can access and edit any list. This feature enables you to have control over all of your mailing lists, while allowing other users to manage individual lists.
* SQL Database Backend: If you have access to an SQL database, then you will probably be able to use it to speed up management of large lists in Subscriber Pro. The script is tested mainly with MySQL and lightly tested with PostgreSQL, but should support many others as well since no database-specific datatypes or functions are used.
* Bounced Address Filtering: If you are able to forward email to a script, then Subscriber Pro can be configured to catch emails that have bounced back. Then, at your discretion, you can delete the addresses that have bounced from your lists.
* Multiple Mail Programs: Subscriber Pro supports both Sendmail and Blat. So, whether you're running Unix or Windows doesn't matter. Plus, support for other programs is easy to integrate.