Mass Business emails from Outlook to gmail customers fail to deliver

Question

I have spent weeks trying to understand and fix the issue below. I am a small business owner and cannot send information to my customer base using Gmail. This is greatly affecting my bottom line. My sales are down 50%. If this continues I will be out of business within the year.

The error message I receive is below...

9/23/2023 10:56:03 AM - Server at MW4PR13MB5990.namprd13.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError'
9/23/2023 10:54:39 AM - Server at gmail-smtp-in.l.google.com (2a00:1450:4025:401::1a) returned '421 4.4.2 Connection dropped due to SocketError'

I found this possible solution on reddit but it is too technical for me to complete on my own. There has got to be a solution on Microsoft's end.

Here is what I found in Reddit

Gmail blocking the IP of the Microsoft hosted Exchange server?

https://www.reddit.com/r/sysadmin/comments/1553i9b/gmail_blocking_the_ip_of_the_microsoft_hosted/

Please get back to me ASAP!

Answer 1

Hi @HappiNest Antiques

This may be the same issue discussed in this thread: https://learn.microsoft.com/en-us/answers/questions/1374851/email-delivery-failed-to-gmail-addresses-only

Please follow the suggestion to contact Outlook.com or Exchange Online support for further investigation on this issue.

Exchange Online: contact the global administrator in your organization to open a service request in Microsoft 365 admin center>Support>Help & Support.

Outlook.com: How to get support for Outlook.com

Thanks for your understanding and sorry for the inconvenience caused.

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