I can not send emails to yahoo accounts

Hello Kirsty

Good day. Thank for posting in the community.

We've received your query and you can expect to receive response from one of our community moderator accordingly.

At this point, we appreciate your patience and cooperation. Thank you.

Sincerely,

Community moderator

Hello Kirsty,

Greetings!
Thank you for posting on Microsoft Community!

In order to provide you with some troubleshooting steps in a more timely manner, we would like to confirm the following information with you:

1. Can you send emails to other external recipients successfully? Could you please also provide the detailed bounce back undelivered report to us after sending emails to Yahoo?
2. If you are using Microsoft 365 Business mailbox, you may need to check DNS records, especially the SPF and DKIM records configured on the domain provider and check if it is correctly added on Microsoft 365 tenant.

For more detailed information, see Set up SPF to identify valid email sources for your Microsoft 365 domain, Use DKIM to validate outbound email sent from your domain in Microsoft 365 and Use DMARC to validate email in Microsoft 365.

3. If you are using Microsoft 365 Exchange online mailbox, you can also ask your IT administrator to perform a message trace for further investigation and provide more error message details to us:

1. Login to Exchange admin center with Microsoft 365 global admin or Exchange admin credentials.
2. In the EAC, go to Mail flow > Message trace. Click Start a trace and then input the sender or recipient email address and check the trace result. Then you can see the cause of not receiving emails externally.

Thank you for your time and cooperation. Wish you have a nice day!

If you need further assistance, feel free to reply us! We will continue to support you!

Thank you!

Community Moderator

Hello - I'm having the same issue as Kristy above. All email recipients with a Yahoo email bounce back, but after a few days. I've included the diagnostic info that is included as part of the email bounce back response. I've hidden the email address of the recipient for privacy purposes. It looks like multiple attempts are made to send the email which causes the undeliverable email to bounce back after a few days.

Your message couldn't be delivered. Despite repeated attempts to contact the recipient's email system it didn't respond.

Contact the recipient by some other means (by phone, for example) and ask them to tell their email admin that it appears that their email system isn't accepting connection requests from your 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 more information and tips to fix this issue see this article: https://go.microsoft.com/fwlink/?LinkId=389361.

Diagnostic information for administrators:

Generating server: MW6PR11MB8309.namprd11.prod.outlook.com
Receiving server: MW6PR11MB8309.namprd11.prod.outlook.com
Total retry attempts: 4

******@yahoo.com
3/3/2024 7:34:02 PM - Server at MW6PR11MB8309.namprd11.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError'
3/3/2024 7:18:08 PM - Server at mta7.am0.yahoodns.net (98.136.96.75) returned '421 4.4.2 Connection dropped due to SocketError'

Original message headers:

Received: from MW3PR11MB4699.namprd11.prod.outlook.com (2603:10b6:303:54::13)
 by MW6PR11MB8309.namprd11.prod.outlook.com (2603:10b6:303:24c::19) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7362.21; Sun, 3 Mar
 2024 17:44:12 +0000
Received: from PH7PR11MB8503.namprd11.prod.outlook.com (2603:10b6:510:30d::14)
 by MW3PR11MB4699.namprd11.prod.outlook.com (2603:10b6:303:54::13) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7362.21; Sun, 3 Mar
 2024 06:42:57 +0000
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none;
 b=YoXiXNuEO4sLnnbaeOr78kV3j30jjqh0IMiY07zJmACktMc4fh/3XgYF8v8/Vo0sIHxG2IHp7IiaxiY4C7wwMF56ZwWEL6HVbjpF7BzcbnDdaxFKUCyj+PXqRAgMHnd+Kmmxw4WD47CkrZMvYSR+7r++WVSijibOPyVapDhHajJn7/FklkLAYKsIjV6+caHceI4V46PK0uuB2ag0/quwot+OtdDqtbfN3uclRYTFKSwIEdHVCGlFpOHuEtnSGFfag/HaKpP7HYp8qH7rUUP2EzfBqpaX6HOt3kwy/gJCXKisMQdtpnsoEVkgdxStUVwe3oNfcGBA8+mb2oOAAw0A+w==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com;
 s=arcselector9901;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1;
 bh=SKJ9yv7ec7o3jeN3VSF+UrM3d0GkiwOb8W1/zYZrxxE=;
 b=c3soD4LPMujZS5RmTi9DO0cQKlbBseXo2P17aUtVB89MFHraNX8WOpb6l4qIe+akZpfAm/0y/ouUvVPUAIzmHeqmAFXjtIMzdFgiHRN4Zv2cBQ8riAfUvtugv1V/2U74u6Exaibk5g96hZMRCMyAZovzhE5UjYcWS+j5UBbWZPSsT/zPMo1gf4O24TTXhYxiuU/atrODpc7r1j75S2LwPaArHo3s5nDGL9XVzVOY1Tkkl5JbzBGyi1NIndUODHoRlHqFMFiCE//Ff++md23r+/RFM62+vtVTu+MJ+JYB9dlI9BG90iQbAYm6Yg9mMQc63X+Oj38QmMiIcpzjcnSwMA==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass
 smtp.mailfrom=lookingglasshomes.com; dmarc=pass action=none
 header.from=lookingglasshomes.com; dkim=pass header.d=lookingglasshomes.com;
 arc=none
Received: from BL1PR11MB5956.namprd11.prod.outlook.com (2603:10b6:208:387::11)
 by PH7PR11MB8503.namprd11.prod.outlook.com (2603:10b6:510:30d::14) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7362.16; Sat, 2 Mar
 2024 19:34:02 +0000
Received: from BL1PR11MB5956.namprd11.prod.outlook.com
 ([fe80::4715:2da6:1971:b649]) by BL1PR11MB5956.namprd11.prod.outlook.com
 ([fe80::4715:2da6:1971:b649%5]) with mapi id 15.20.7362.010; Sat, 2 Mar 2024
 19:34:01 +0000

If you use custom domain name for your business, check your DNS records (SPF, DMARC etc).

Hi

I am having the same issue as the two posters above. I cannot send emails to any yahoo addresses. They appear to send and then a couple of days later I get an undeliverable report. I can send emails to other email addresses with no problem.

This has been going on since before Christmas. Please can someone help to resolve this.