How can I locate a computer with a spam virus

Posted on 2011-10-07
Last Modified: 2012-05-12
I have a network with about 50 computers. I have a Fortigate with an active Fortinet subscription and I have created a firewall rule that only allows smtp from our SBS 2003 server. Recently our email server was blacklisted so I signed up for a mail relay service. After about a month the mail relay service said we have a computer sending spam and they had to shut down our relay service until it is resolved. How can I find which computer is sending spam without going to all 50 computer and ruining an anti virus scan?
Thank you for your time and expertise.
Question by:dmader
    1 Comment
    LVL 28

    Accepted Solution

    Is the spam from a particular user as the sender; that would be a good way to ID them. If not, then you could use a utility like Wireshark to monitor traffic to ID the offending machine. Another possibility is to shut them all down one by one.

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