Charter and Cox contacts

Mark Milhollan mlm at
Tue May 14 18:22:41 UTC 2019

On Mon, 13 May 2019, Stephen Satchell wrote:
>On 5/13/19 12:11 PM, daniel at wrote:

>>Does anyone have contacts at Charter (Spectrum) and Cox? For some reason,
>>our IP has been blocked by them and our customers are unable to send email
>>via their charter/cox accounts. Thanks
>Would you be talking about port 25/tcp outbound?  Lots of ISPs will
>block port 25 as a rule;

If this is the case, that your customers cannot use your mail servers to 
relay mail then provide port 587/TCP (SUBMISSION) or even 465/TCP 
(SMTPS, deprecated).

If you mean that your mail servers can't send mail to Charter and Cox 
addresses, then indeed you need to find out what happened, fix it then 
request removal from their (and other) blacklists for which contacts 
there would be helpful (I am not one).


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