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Outgoing Mail

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I am suddenly having trouble sending emails to a particular email address. Cox is my internet provider and I have explored the problem with them. It appears to be a Thunderbird problem. When I send a message to this particular site, I get the following message: " An error occurred while sending mail. The mail server responded: <mustangmaggie@cox.net> message rejected. Refer to Error Codes section at https://www.cox.com/residential/support/email-error-codes.html for more information. AUP#CXSNDR. Please check the message and try again.

Thanks in advance for your help.

I am suddenly having trouble sending emails to a particular email address. Cox is my internet provider and I have explored the problem with them. It appears to be a Thunderbird problem. When I send a message to this particular site, I get the following message: " An error occurred while sending mail. The mail server responded: <mustangmaggie@cox.net> message rejected. Refer to Error Codes section at https://www.cox.com/residential/support/email-error-codes.html for more information. AUP#CXSNDR. Please check the message and try again.'' Thanks in advance for your help.

All Replies (2)

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Cox is your internet provider and you are obviously sending your mail from another email domain/and email address not containing @cox.net. Cox feels that domain is not configured correctly.

We see a lot of that sort of thing here. Mostly from cheap as chips hosting providers where folks do DIY domain configurations. What is the domain name?

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Hi and thank you for responding so quickly. Actually, cox.net is the domain. I don't access my emails through Cox, though, as I use Thunderbird for that purpose. Does that make sense?