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My customers are not getting confirmation emails. They are being blocked.
This is in the bounced email notification.
" ----- Transcript of session follows ----- .. while talking to hotmail-com.olc.protection.outlook.com
>> MAIL From:<mrjim@mrjims.pizza>
<<< 550 5.7.1 Unfortunately, messages from [208.74.8.144] weren't sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [VI1EUR04FT014.eop-eur04.prod.protection.outlook.com]
Getting same message [with one word changed] on emails sent to outlook.com
I cannot contact anyone at Microsoft that knows what is going on. Was told by an MS Exchange support tech that there is no way for MS to block them.
I am close to my email provider support team, I have their cell phone numbers. And they can't find out what's going on. Nor can they contact MS.
Any ideas would be helpful.
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Hi, I'm here to confirm with you if your issue has been resolved. If the problem is successfully solved, you can share your solution and mark them or the helpful reply as answer, this will make answer searching in the forum easier and be beneficial to other community members as well.
Hello, I'm here to confirm that is there any progress in your question?
Hi @MrJim Johnson ,
Based on your error message “550 5.7.1”, you can refer to this document:
https://learn.microsoft.com/en-us/exchange/mail-flow-best-practices/non-delivery-reports-in-exchange-online/fix-error-code-550-5-7-1-in-exchange-online
You can get in touch with Outlook Sender Support via going to this direct link:
https://support.microsoft.com/en-us/supportrequestform/8ad563e3-288e-2a61-8122-3ba03d6b8d75
In addition, please pay attention to protect your private information, thank you.
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