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ctwalters83294597's profile

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1 Message

Wednesday, February 8th, 2023 1:57 PM

Email server blacklisted

host[]said: 553 5.3.0 alph733 DNSBL:RBL 521< >_is_blocked.Forassistance forward this error to (in reply to MAILFROM command)

I have emailed the above address with no result. My server is not on any other blacklist. I do not relay messages to any of att's servers.

Community Support


210.2K Messages

1 month ago

Hey @ctwalters83294597. Thanks for reaching out to us about your email service being blacklisted, and we'd be happy to help you.


In order to get further assistance with your email service being blocked, you'll need to send another email to the email address. If you send too many emails in quick succession then it can be marked as spam by them. You can also check here for more information about getting help from our AT&T Mail postmaster about your email server.


Please reach back out to us if you have any future questions. Thanks for contacting the AT&T Community Forums.


Robert, AT&T Community Specialist

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