>Is there more than one kind of email server? For example, I use a VFP routine that reads the email from a linux-based email server, I don't know nothing more than its IP address, the port, the email address, its account, and its password. Oh, and that routine I copied and modified from an article that was published in UT Magazine some time ago.

Notification can be implemented on the email server itself, if you have acces to it and know how to do that. Otherwise you'll have to poll the server on timer chcking for messages. The polling interval will depends on how much time you can allow between message arrival and processing.