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error message "Your message wasn't delivered. Despite repeated attempts to deliver your message, a connection to the remote server was closed abruptly.
Contact the recipient by some other means (by phone, for example) and ask them to tell their email admin that it appears that your email system is unable to connecto their email system. Give them the error details shown below. It's likely that the recipient's email admin is the only one who can fix this problem.
For Email Admins
This often indicates the recipient's firewall SMTP fixup setting or other firewall settings are preventing the SMTP protocol negotiation from succeeding.
For more information and tips to fix this issue see this article: https://go.microsoft.com/fwlink/?LinkId=389361.
For Yahoo: returned '550 5.4.318 Message expired, connection reset (SuspiciousRemoteServerError)(450 4.4.318 Connection was closed abruptly (SuspiciousRemoteServerError))'
3/8/2024 8:44:42 PM - Server at mx-eu.mail.am0.yahoodns.net (188.125.72.73) returned '450 4.4.318 Connection was closed abruptly (SuspiciousRemoteServerError)'
For sky: returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError'
3/8/2024 8:39:33 PM - Server at 188.125.72.73 (188.125.72.73) returned '421 4.4.2 Connection dropped due to SocketError'
I cannot ask all my contacts that have yahoo or sky accounts to change their firewall settings. There seems to be a problem with Microsoft!
Sending, receiving, and organizing email in Outlook on the web for business
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Thank you for this information however it would be super helpful if the links that your posted actually explained where to access all these settings within the Admin Center.
This is really pointless information that doesn't help the average person much.
Are you able to explain or provide clear information on this please.
The DKIM record that within 365
This is under security admin center> policies> threat policies> DKIM
You need this apparently to be setup from the 365 tenant itself.
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If your email address ends with outlook.com or hotmail.com, your problem is something else and it isn't something you can do to fix. It is Microsoft's responsibility to fix the issue. I highly suggest changing your mail provider to other.
Just to say I have checked and verified my MX, SPF and CName records in my domain host's DNS settings and they were all correct and matched what Microsoft requires. HOWEVER, I had not applied the DKIM outbound encryption which it seems Yahoo and AOL (both the same company) now require, as do Sky and also, it seems BTinternet too. This isn't a Microsoft problem, it is theirs, but in reality it's likely to be something all providers will be requiring in future to prevent or reduce SPAM and phishing attacks.
I have now applied DKIM encryption in my Microsoft email settings (as per their guide earlier), plus I have added the two extra CName records with my domain host's DNS settings and I am testing now, but my emails are definitely still working. I just need to verify Yahoo and AOL recipients etc get them too, which I believe they will now.
Sadly, this complexity is the price we all pay to protect ourselves from those who are less than scrupulous
“Enable and add DKIM to my domain” that might as well be written in Swahili for all it means to me!
I am a pensioner using the Mail app on my iPad to send emails from my outlook account (******@live.co.uk) to my sister (who uses yahoo). Said emails started bouncing 3 days ago, I have done nothing so something changed at either the Microsoft or Yahoo server end. I would like that change backed out so she can receive my emails once again.