Request for IP Delisting and Block Removal

Mario 0 Reputation points
2026-08-18T10:50:17.92+00:00

Hello,

once in several months we are unable to send emails to domains live, outlook and hotmail.

This is happening atleast for 2 years now.

Every time we send request for delisting to https://sender.office.com/ and https://olcsupport.office.com/

We never get reason why our IP is blocked.

We checked our IP on several blacklist sites, on none of them was any issue.

Exchange | Exchange Server | Other
Exchange | Exchange Server | Other

A robust email, calendaring, and collaboration platform developed by Microsoft, designed for enterprise-level communication and data management.Miscellaneous topics that do not fit into specific categories.

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  1. Demi Nguyen 1,585 Reputation points Independent Advisor
    2026-08-18T11:24:02.6233333+00:00

    Hello Mario,

    This account restriction is handled by Microsoft’s backend account review system. Since you have already submitted the online locked account review form, you have completed the correct step.

    If the request was closed or you need the account to be reviewed again, please use the same form to submit a new review request.

    One possible cause may be unusual or suspicious activity associated with the network or public IP address being used. For example, if several users share the same public IP address and another user on that network generates abusive or spam-like traffic, the security system may also flag other activity coming from the same network. However, I cannot confirm whether this is the cause in your case because the related backend information is not available in this forum.

    As an additional troubleshooting step, you can contact your Internet service provider and ask whether the public IP address can be refreshed or changed. You can also test from another trusted network.

    If you would like more information about why the account was restricted or need further assistance:

    When contacting Support, please include the full non-delivery report, SMTP error code, affected public IP address, recipient domain, and the approximate time of the failed delivery. These details will help the appropriate team review the case more effectively.

    Please note that this community is primarily a user-to-user forum. Forum participants do not have access to Microsoft’s backend sender-reputation systems and cannot view the specific reason an IP was blocked or remove the restriction directly.

    I hope the appropriate support team can provide further guidance. Please feel free to update this thread if you receive any additional information.

    Kind regards,


    Note: Please follow the steps in documentation to enable e-mail notifications if you want to receive the related email notification for this thread. 

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