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The other day, Outlook stopped being able to send email.  I did not upgrade any software (McAfee security/firewall/AOL/etc.) nor change any settings knowingly.


While I can receive messages fine in Outlook, I cannot send emails that I personally compose.  However, if I go into account settings in Outlook and perform a test send, that works fine.  Additionally, if I send emails straight through AOL (either via the web AOL or the fat client version) they go through as well also.  So, the problem seems to be localized to when I personally compose the email via Outlook and hit send.


The exact message I receive is: 

Sending' reported error (0x800CCC61) : 'Your outgoing (SMTP) e-mail server has reported an internal error. If you continue to receive this message, contact your server administrator or Internet service provider (ISP).  The server responded: 521 5.2.1   521 AOL will not accept delivery of this message '

My account settings in Outlook are configured for port 587 and using TLS.  This has not changed from when it used to work.

Any help would be appreciated.



Thank you so much for your reply!  I really appreciate it!  I did follow all of your steps/steps based on your links, but still it did not work.  As such, I contacted AOL and asked them for support.  They were able to help me to get this to work.  Apparently, there was either some change in Outlook or AOL (not sure which) where if my name on the Outlook Account included an "AOL", AOL would stop accepting the emails.


Seems like a silly thing to cause the problem, but apparently it has caused problems with many people, not just myself.


Again, thank you for taking the time to try and help.



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Question Info

Last updated April 28, 2020 Views 5,815 Applies to: