I had a support case this week in which a customer’s domain was being Blacklisted, because of spam from his SMTP server. Upon further investigation, he found that the mail server showed no¬†evidence of spam mail going through the server.

I had the customer open his Scrutinizer NetFlow analysis tool via the web interface and create a custom report that looks at SMTP traffic on port 25 and the Internet router, through which all traffic passes. We viewed the report to find all outbound traffic on TCP port 25. Guess what we found? An unauthorized host sending mail through his network.

He was able to identify the compromised host and fix the issue in a timely manner.

Jamie Lee author pic

Jamie Lee

Jamie Lee is the west coast Regional Manager at Plixer. He works with prospects to solve the unique needs of their network and visits existing customers to assist with training. He enjoys developing new partnerships and building long-lasting relationships with his clients. Jamie loves the outdoors and his favorite hobbies include fishing, hiking, and football.


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