emails are bouncing back when sending to yahoo

Hello mpur,

Good day to you and thanks for your post in Microsoft community.

Regarding your post, may i are you sending email from Micrsooft365 business account? If so, based on the error message, we have checked and found official article, please check with SocketError when sending or receiving email messages - Exchange | Microsoft Learn and further assistance we recommend to contact Microsoft Technical team by either open ticket or phone support Get support - Microsoft 365 admin | Microsoft Learn (Note: only admin can open ticket, so if you don't have admin permission, kindly contact your admin and if you purchase Microsoft services from partner, please contact your partner).

If your sending email account is belonging from outlook.com/live.com/hotmail.com side, please reply back to us, so we can involve dedicated team for further assistance.

Thank you for your time and cooperation.

Sincerely,

Ankita Vaidya

Hello mpur,

Good day!

Thank you for posting to Microsoft Community. We are glad to assist.

We are looking into your situation and we need sometime to do further research on this. Will update the thread shortly.

Appreciate your patience and understanding and thank you for your time and cooperation.

Sincerely,

Microsoft Community