We are using a Sonicwall E5500 firewall with all security services turned on, along with the McAfee antivirus enforced client. We are also using a Sonicwall anti-spam appliance (VMware). Many of our outgoing e-mails are bouncing because our main IP address is blacklisted by Spamhaus, apparently because something on our network was trying to contact one of the servers taken over by the federal government yesterday. The strange thing is that the e-mail appliance - which all e-mail goes through - is at a different public IP address than the one that's blacklisted, yet the e-mail is getting bounced.
Anyway, I'm trying to figure out how to find the culprit on the network? I have been unable to determine what port numbers or IP addresses to have the firewall look for in the packet monitor. (The Spamhaus site just tells me I'm blacklisted, but...