Good morning - we are currently investigating two blacklists from large ISPs targeting one IP address on the ExchangeDefender network. Two services are identified as Verizon and FrontBridge and we have opened requests to be removed from both along with any data that might help us find out why the lists were put in place to begin with given our 0 tolerance for SPAM. The rejections are marked by:

< mail157-dub-R.bigfish.com #5.0.0 X-Postfix; host    winse-6216mail6.customer.frontbridge.com[131.107.115.215] said: 550 5.7.1    External client with IP address 65.99.255.232 does not have permissions to  submit to this server. Visit http://support.microsoft.com/kb/928123 for more information. (in reply to end of DATA command)>

 

<outbound2.exchangedefender.com #5.5.0 SMTP; 571 Email from 65.99.255.232 is currently blocked by Verizon Online’s anti-spam system. The email sender or Email Service Provider may visit http://www.verizon.net/whitelist and request removal of the block.>

In the meantime, you can change your outbound smarthost to outbound1.exchangedefender.com if you experience the problems above.

On the funny side: We find it hilarious that Microsoft is linking to their own KB articles in the rejection note for a problem that is caused on their own servers - how about something more helpful like postmaster or delisting contact address or URL! Even more surprising is that Microsoft FrontBridge is running on an open source Postfix mail platform, not a Microsoft one.

We will update you on the delisting process as we get more information. The problem should not impact many senders as 65.99.255.232 is just one of the nodes in our outbound network.

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