We are suddenly getting a large amount of outgoing messages (230000 so far) in the SMTP connector on our SBS 2003 server. Messages are showing to be sent from multiple unknown senders so I am unsure as to where they are coming from. I have changed the SMTP to forward the messages to thru a bogus ip address and am in the process of removing the the messages. (A Long and arduous process!) But I need to track down where they came from and how to prevent it in future. Help would be appreciated.