Please configure B2B collaboration settings correctly; suspicious activity

Helen 0 Reputation points
2026-05-20T14:10:15.5966667+00:00

I am a very, very SME. Only me. There is no ICT helpdesk in my company, only me. I cannot share anything and receive the following error: Please configure B2B collaboration settings correctly and troubleshoot first, "https://aka.ms/b2b-troubleshoot". Error from Entra B2B: At least one invitation failed. Error: ResponseStatusNotOK, message: Invitations are blocked for this directory due to suspicious activity. Please contact Microsoft support for help..

I have been contacting MS helpdesk daily since the beginning of April and no one seems to know what to do to help. Someone there gave me a workaround - to copy a link and email it but that doesn't work because the guest can't sign into MS without a school or work account.

I don't know what to do to fix it. Can someone help?

Microsoft Security | Microsoft Entra | Microsoft Entra External ID

1 answer

Sort by: Oldest
Most helpful Newest Oldest

  1. AI answer

    2026-05-20T14:10:30.77+00:00

    The error indicates that guest invitations are being blocked at the directory level and that Microsoft has already flagged the tenant for suspicious activity. This is not something that can be fixed from the portal or by changing normal B2B settings; it requires direct intervention from Microsoft support.

    From the provided information, the only supported remediation path is:

    1. Open or escalate a support ticket with Microsoft specifically for “invitations are blocked for this directory due to suspicious activity.”
    2. Work with the Microsoft support/Data Protection or security team to review and clear the block on the tenant so that invitations can be re-enabled.

    If there is no other global admin in the tenant who can help, the pattern from similar “locked/blocked tenant” cases is that Microsoft support must validate ownership of the tenant and then remove or adjust the block on the back end. This is not configurable by customer-side settings.

    Until Microsoft removes the block, B2B invitations and normal external sharing will continue to fail with the ResponseStatusNotOK error, regardless of how external collaboration settings are configured.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

    Was this answer helpful?

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.