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Email sent to Hotmail accounts gets returned as "Delivery Status Notification (failure"

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Hi, I hope someone can help with this. All of a sudden I can't send to Hotmail addresses - was working fine up until yesterday. Here's the full message that I get:

The following message to <jakenicoll@hotmail.com> was undeliverable. The reason for the problem: 5.1.0 - Unknown address error 550-"5.7.1 Unfortunately, messages from [134.153.136.23] 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. [DB3EUR04FT045.eop-eur04.prod.protection.outlook.com]"


Reporting-MTA: dns; esa03.ucs.mun.ca

Final-Recipient: rfc822;jakenicoll@hotmail.com Action: failed Status: 5.0.0 (permanent failure) Remote-MTA: dns; [104.47.12.33] Diagnostic-Code: smtp; 5.1.0 - Unknown address error 550-"5.7.1 Unfortunately, messages from [134.153.136.23] 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. [DB3EUR04FT045.eop-eur04.prod.protection.outlook.com]" (delivery attempts: 0)


Any thoughts or help is much appreciated. Got the same result with another friend who has a Hotmail account. Thanks!

Thanks Adrian

Hi, I hope someone can help with this. All of a sudden I can't send to Hotmail addresses - was working fine up until yesterday. Here's the full message that I get: The following message to <jakenicoll@hotmail.com> was undeliverable. The reason for the problem: 5.1.0 - Unknown address error 550-"5.7.1 Unfortunately, messages from [134.153.136.23] 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. [DB3EUR04FT045.eop-eur04.prod.protection.outlook.com]" Reporting-MTA: dns; esa03.ucs.mun.ca Final-Recipient: rfc822;jakenicoll@hotmail.com Action: failed Status: 5.0.0 (permanent failure) Remote-MTA: dns; [104.47.12.33] Diagnostic-Code: smtp; 5.1.0 - Unknown address error 550-"5.7.1 Unfortunately, messages from [134.153.136.23] 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. [DB3EUR04FT045.eop-eur04.prod.protection.outlook.com]" (delivery attempts: 0) Any thoughts or help is much appreciated. Got the same result with another friend who has a Hotmail account. Thanks! Thanks Adrian

Chosen solution

adrian.house said

Reporting-MTA: dns; esa03.ucs.mun.ca Please contact your Internet service provider since part of their network is on our block list (S3150).

This is a problem related to your email provider esa03.ucs.mun.ca. The Memorial University probably has a IT department that manage the email server. I think you should contact them and let them know their server has been blocked by Hotmail.

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All Replies (2)

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Suluhisho teule

adrian.house said

Reporting-MTA: dns; esa03.ucs.mun.ca Please contact your Internet service provider since part of their network is on our block list (S3150).

This is a problem related to your email provider esa03.ucs.mun.ca. The Memorial University probably has a IT department that manage the email server. I think you should contact them and let them know their server has been blocked by Hotmail.

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Thanks a lot Danny. I spoke to them today and apparently someone sent out a lot of spam so Microsoft blocked one of their servers. They said they're working on the issue. Cheers, Adrian