Skip to main content
AT&T Community Forums
The epic new Samsung Galaxy S21 5G is available for preorder now!

New Member


1 Message

Fri, Nov 27, 2020 10:47 PM

error when sending email to


R=default_mx_router T=remote_smtp []:25 I=[]:42656: SMTP error from remote mail server after MAIL FROM:<[email scrubbed]>: 553 5.3.0 alpd682 DNSBL:RBL 521< >_is_blocked.For assistance forward this error to


any ideas why?



Brand User

Community Support


144.5K Messages

2 months ago

Hi, @leohamel.


It looks like your email was blocked and possibly blacklisted. To get this resolved, please email the abuse team at the provided email address and request to have the block removed.

Thanks for reaching out. If you need help with anything else, let us know.


Aminah, AT&T Community Specialist

Still need help? Ask a question! Our 1.4 million members typically respond within 1 hour.

*I am an AT&T employee, and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.

Get started...

Ask a new question