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getting these two error messages when sending to yahoo
1/11/2024 3:34:15 PM - Server at DS0PR14MB7526.namprd14.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError'
1/11/2024 3:24:36 PM - Server at PH0PR14MB6715.namprd14.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to ConnectionReset'
Using Classic Outlook on Windows for personal email, calendar, and contact management
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.
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It affects users who use custom domains (not outlook.com or hotmail.com). If that is the case, your DNS records (SPF, DMARC, DKIM) may have something to do with the problem. If you tell us your custom domain name (not the entire email address), we may be able to check if you have those necessary DNS records.
I had same issue but GoDaddy (my domain provider) was well aware of issue, updated my DNS settings and now all e-mails are going through.
Yes, Yahoo mail has new security requirements for the sending domain, specifically a DMARC statement in the DNS. I got this fixed a couple weeks ago and by creating a ticket with M365 support.
And you really need to do it because soon Google will make the same changes for GMail.
Same here. I am now getting bounce backs from a Yahoo account that I've successfully emailed for years.
I'm still reviewing message boards but, are there any solutions aside from saying it's on Yahoo's end?
This started on my account last week. I agree with Louise, we're paying too much for the service for emails not to be properly delivered.
There is no issue with Gmail or corporate accounts. I am only getting the bounce back from Yahoo, AOL & Verizon.
Microsoft we need this resolved ASAP