According to Spamhaus.org, Verizon.net is one of the largest ISP networks that allows Virus and Trojan activity on their Network. Verizon, however, says it plans to put measures in place to prevent it from being used as a home to so many spammers. According to Security Fix Spamhaus currently includes 225,454 U.S. based Internet addresses on its CBL. Of those, nearly one-quarter — almost 56,000 — are assigned to Verizon.net.
At MxToolBox we always encourage our customers to secure their network by locking down port 25 to only allow outbound traffic from their mail server and to test to make sure that their server cannot be used as an open relay. If you are listed on the CBL it is more than likely because of a virus or trojan that is sending out spam from your network without your knowledge. We would highly recommend installing Ad-Aware, Spybot Search & Destroy, and an anti-virus package in on all Windows workstations as well as the mail server. This will ensure that you are scanning for this activity and help prevent you from having an issue.
If you still continue to have issues sending mail, we highly encourage you to contact one of our blacklist specialist which can tell you about our Business Enterprise Blacklist Protection Email Services.
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