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Starting this week, our emails to yahoo and aol accounts are not being delivered, but emails to other email accounts are working. Here is one of the yahoo error message: 1/12/2024 9:27:16 PM - Server at SJ2PR02MB10076.namprd02.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError' 1/12/2024 9:26:15 PM - Server at mta5.am0.yahoodns.net (67.195.204.73) returned '421 4.4.2 Connection dropped due to SocketError'
And here is the aol error message: 1/12/2024 9:27:38 PM - Server at PH0PR02MB7367.namprd02.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError'
1/12/2024 9:15:15 PM - Server at mx-aol.mail.gm0.yahoodns.net (67.195.204.80) returned '421 4.4.2 Connection dropped due to SocketError'
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.
the sender refers to the smtp server in that specific message, which is hotmail. The return for too many recipients has a different code
make a support case. See if they can help you setup dkim or let you know if it's not available. This message is simply saying that hotmail is sending too many emails not to have dkim enabled.
The issue is dns related, but in the cases of custom domain names you have to manage the DNS manually. There is an option to have O365 manage dns but that is another topic. For free service providers, you must configure the services for dmarc and dkim or reach out to support if you don't have those options. Once these options are enabled, the free email providers will update their dns. It will take 24-48 hours to update and propagate on free providers. At the end of the day, the emails are rejected because or missing or misconfigured DMARC, DKIM, or SPF records. If all three were configured correct then the email will not be rejected.
I believe the reply I just posted on the next page also answers your question, but let me know if it doesn't
a custom domain email is not linked to hotmail. You can buy a business plan and link custom domains in o365 or outlook.com. In cases of free email providers, you will need to look up how to configure dmarc and dkim settings on that providers email. They will handle the spf automatically. Not all free email services offer this. You can verify your records by using tools at mx****