I have an SBS 2003 Exchange Server running behind a firewall, with a couple of client machines running XP. My ISP has shut down port 25 outgoing several times, and is telling me that we are sending something like 2,000 emails in three hours. Sounds like a virus to me, although we are using an enterprise level anti virus and mail protection suite, and nothing is being reported. Also, there are no complaints from other ISPs or anyone else about spam coming from us.
The ISP tech support is asking me to monitor our email outgoing, to see what is happening (they refuse to do that for us).
Are there any good tools for doing this, either built into Exchange or that I can get, which produce clear and simple reports like a list of outgoing emails, their originating IP and email addres and destination IP and email address, so I can figure out what is going on ?