If you’ve received a 554 error message, you’ve been blocked from emailing the Comcast network because your email server is not properly identifying itself when connecting to our servers. This identification process is known as Reverse DNS. Individuals who send spam commonly hide their Reverse DNS to avoid being detected when sending email, which is why these email servers are blocked.
Solution Code
Comcast is not blocking your email server's IP address. If you’ve received this message, simply contact your email administrator and have your Reverse DNS configured properly.
When contacting the administrator, be sure to include the information from your error message – it will have information that may be needed to resolve the issue.
Additional information
Visit our Online Support Center to find common solutions.
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