We are running Exchange 2003 SP2 Enterprise on a Windows 2003 SP1 box (all current updates). This is the only server in our company and has but a single SMTP connector to our e-mail filtering software which handles all actual sending and receiving of internet e-mail.
Per the suggested article in other posts (http://www.msexchange.org/tutorials/MF009.html
) I have configured a mail enabled security group to restrict users from sending over the SMTP connector. I added the group to the reject portion on the connector, made the necessary registry changes and restarted the services. Didn't work. I enabled the connection and sender filtering on the virtual server and restarted the virtual connector, and even rebooted the server to no avail. I have followed the directions in the article exactly, but the account I am testing with can send freely over the only SMTP connector we have. I am at a loss. We need to find a relatively easy and foolproof way to stop users who should not be able to send external e-mail, and this looked like the right solution.