North American Network Operators Group

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RE: Blacklisted SMTP

  • From: Frank Bulk
  • Date: Tue Apr 25 11:30:48 2006

This posting on might add some background to your issues:

From: [email protected] [mailto:[email protected]] On Behalf Of Chris Riling
Sent: Monday, April 24, 2006 3:12 PM
To: [email protected]
Subject: Blacklisted SMTP


     What's up with VZW blacklisting a large amount of IP space on their MXes? I have tried sending mail to from several boxes on Cogent's network to no avail... Is Cogent on the "bad boy list" yet again? Anyone have a useful contact there? We're not able to correspond with our sales rep via email and they're losing business. I have contacted some NOC engineers with no luck...

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