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

Koes 350 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?

Microsoft Exchange Online Management
Microsoft Exchange Online Management
Microsoft Exchange Online: A Microsoft email and calendaring hosted service.Management: The act or process of organizing, handling, directing or controlling something.
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  1. Casey Witham 0 Reputation points
    2023-10-11T13:16:59.3433333+00:00

    Comment removed.

    0 comments No comments

  2. Gençosman Öztürk 0 Reputation points
    2023-10-11T13:18:09.1333333+00:00

    same problem in Türkiye

    plz add to whitelist

    193.36.184.213


  3. kc 0 Reputation points
    2023-10-11T13:21:39.5066667+00:00

    please Whitelist our IPs :

    103.230.125.210

    103.230.125.211

    103.230.125.212

    103.230.125.215

    103.230.125.216

    103.230.125.217

    0 comments No comments

  4. Didier BIBAL 10 Reputation points
    2023-10-11T13:21:50.6133333+00:00

    Hi. Whitelist for 185.29.40.20 please. Thanks

    0 comments No comments

  5. Silvio Spagnoli 0 Reputation points
    2023-10-11T13:22:07.0866667+00:00

    same problem in Italy

    plz add to whitelist

    78.4.31.53

    212.28.160.0/25

    0 comments No comments

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