Forum Discussion

Ole_Dog's avatar
New Contributor
3 years ago

Can not send emails from Thunderbird

Can not send email from Thunderbird. Keep receiving the following: Sending of the message failed.
An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: cmsmtp blocked. Refer to Error Codes section at for more information. AUP#CXDNS.

Help, please.

1 Reply

Replies have been turned off for this discussion
  • Bruce's avatar
    Honored Contributor III

    I will presume the configurations of these email clients (Outlook, T-bird, etc) are not new and probably have been successfully connecting to for years...if not a decade.

    Cox had recently changed something.  PTR records are like ID cards for email servers..."Who are you"? it begs the question to what is Cox comparing these IP addresses?

    I wonder if email clients on cell phones connected to a cellular network are also having problems.