So we are running GFI Mail Essentials currently. It was being used for Spam Filtering along with a "News Letter" type of ListServ which is built in. I have migrated all of our Spam filtering for Exchange over to our Sonicwall and that appears to be working well.
I have disabled all of the SMTP Event Sinks for GFI from running while scanning mail. I want to totally ditch he GFI install, because it runs a few processes that use a few hundred MB of ram. So the only thing the GFI is doing at this point is listening for mail for the newsletter.
Here is how it works.
Person sends e-mail to : email@example.com - They receive e-mail to reply back to be added, they do, they are added in our system and a confirmation e-mail is sent
Person sends e-mail to - firstname.lastname@example.org - They receive e-mail to reply back to be removed, they do, they are removed and a confirmation e-mail is sent.
Internal user that is "granted" access in the GFI newsletter section, sends e-mail to email@example.com, it generates outbound e-mail to each person on the list.
It's pretty simple works good, and also removes any subscribed e-mail addresses if they come back rejected/unknown.
So what I am looking for is something that is similar, that runs on the Exchange box, no PHP/Web-based stuff. And free if possible.