We are being affected by viruses on workstations that send mail thru an SMTP generated by the virus, bypassing our exchange server. As a result, we get blacklisted before we know it. I can remove the entire server where exchange is from the network and mail is still flowing out. My question is this: is there a method of blocking E-Mail sent thru port 25 by anyone but exchange? How can we stop these situations?
Thank you in advance for your assistance. J.P. Lacasse ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~