E-Mail sending to Offcie/Microsoft365 customers not possible - 451 4.7.500 Server busy

Koes 360 Reputation points
2023-10-11T10:38:11.0866667+00:00

Hi,

since this morning 5 am we are not able to send E-mails to office365/Microsoft365 Customers. Our Mails are stuck in our own queue and get the response: host customername.mail.protection.outlook.com 451 4.7.500 Server busy please try again later wit 193.228.149.133 S77719

Can someone check, why we are on an throtteling list with our E-MailServer and remove please?

Exchange Online
Exchange Online

A cloud-based service included in Microsoft 365, delivering scalable messaging and collaboration features with simplified management and automatic updates.


175 answers

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  1. Clouduck 0 Reputation points
    2023-10-13T13:46:03.63+00:00

    185.150.131.117 - Turkey

    Please add to whitelist.

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  2. Burak Delice 0 Reputation points
    2023-10-13T13:35:29.8233333+00:00

    212.109.114.166 - Turkey

    Add me!

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  3. Simone De Rossi 0 Reputation points
    2023-10-13T12:50:26.61+00:00

    @outlook.com

    Please whitelist the following ip: 2.33.114.18

    from Italy

    thanks

    Best Regards

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  4. Simon 0 Reputation points
    2023-10-13T08:13:03.3466667+00:00

    Vietnam is also experiencing the same situation. Please help add whitelist

    112.213.93.83

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  5. Lakshmanan Duraisamy 0 Reputation points
    2023-10-13T07:00:52.18+00:00

    Is this issue fixed? still we have same issue mails are stuck in queue! Please advise @outlook.com

    Date Received: 10/13/2023 9:53:58 AM

    Expiration Time: 10/15/2023 9:53:58 AM

    Last Error: 451 4.7.500 Server busy. Please try again later from [XXX.XX.XXX.XX]. (S77719) [DM3NAM06FT009.Eop-nam06.prod.protection.outlook.com 2023-10-13T06:54:02.392Z 08DBCB333D3815CC]

    Queue ID: HOSTNAME\89

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