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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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Multiple SPF records could be your problem. Delete one of them (GoDaddy knows how to do it). That should take care of it.
GoDaddy is my domain provider. I've been reading on their site on how to make the changes. Thank you!
To be clear, Microsoft is my email provider through Office 365, but my domain registrar is Google (which sold that business to Squarespace, and it will be there soon). I had to make DNS changes using Google DNS, although Microsoft told me what changes were needed.
So you may need to deal with two companies. Most people probably use the same company for both services.
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.
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.