Our domain has a known manufacturer's firewall through which all email traffic must flow before reaching our Exchange Server.
We subscribe to Anti-Virus and Anti-Spyware services from this firewall manufacturer. Therefore, all email receives a scan while passing through this device. If Spam is detected by the firewall, the message is tagged and the word "SPAM" is added to the subject line. The email then passes through to the Exchange Server for delivery to the email recipient.
The firewall can be set to "discard" rather than "tag" the email as it comes through. However, the "discard" action can only be set for SMTP traffic, whereas POP3 traffic can only be set to "tag". I'm assuming that POP3 traffic would be emails from the outside world delivered to our domain via email senders using @Hotmail.com, @yahoomail.com, etc.
I would like to stop delivery of these messages to the email recipient.
I'm wondering if the Exchange Server can be set to recognize a key work in the subject line (in my case the word "SPAM") and simply NEVER deliver the email?