Account Creation Blocked

Have the file owner remove the existing share and reshare it directly to the user’s exact @memorialhealthcare.org address so Microsoft Entra B2B creates or matches a guest account and offers email one-time-passcode authentication instead of requiring a new personal Microsoft account.

Recommended resolution

Ask the sender or the sender’s Microsoft 365 administrator to:

1. In OneDrive or SharePoint, select the file or folder and open Manage access.
2. Remove the existing recipient or link.
3. Select Share → Link settings → Specific people.
4. Enter the user’s full @memorialhealthcare.org address and send a new invitation.
5. Have the user open the new invitation, choose Send code when prompted, retrieve the code from Google-hosted organizational email, and enter it.

For new external sharing in commercial tenants, SharePoint and OneDrive use Microsoft Entra B2B. Resharing creates the required guest account, and users without another supported identity can authenticate using an emailed one-time passcode rather than creating a Microsoft account.^1^ The code is valid for 30 minutes, and the authenticated session lasts 24 hours.^2^

The Google choice is not required for this method. Google federation is a distinct identity-provider configuration; email OTP is the fallback when no managed Microsoft account, personal Microsoft account, federation, or other password-backed authentication method applies.^2^

Since different browsers, private sessions, and networks have already failed, repeating those client-side tests is unlikely to address this sharing workflow.

If the sender cannot select “Specific people” or OTP never appears

The sender’s Microsoft 365 administrator must check the resource-owning tenant, not Memorial Healthcare’s Google configuration:

1. Open SharePoint admin center → Policies → Sharing.
2. Confirm SharePoint and OneDrive external sharing is set to at least New and existing guests.
3. Review:
   • Site-specific sharing restrictions.
   • Domain allow/block lists for memorialhealthcare.org.
   • Microsoft Entra external-collaboration restrictions.
4. Reshare the item after correcting the applicable restriction.

The New and existing guests level permits recipients to sign in with a work/school or Microsoft account, or verify their identity using a code. Site settings can be more restrictive than organization settings, and Microsoft Entra restrictions can override SharePoint or OneDrive settings.^3^

If the content is not sensitive and the sender’s policy permits unauthenticated access, the sender can instead create an Anyone with the link link. This option is only available when the tenant and site permit the Anyone sharing level, and it provides less recipient accountability.^3^

If this is personal OneDrive rather than organizational OneDrive/SharePoint, the sender may need either an Anyone link or a recipient who has a Microsoft account; Microsoft documents that some “Specific people” sharing cannot be used with recipients who lack one.^4^

About the former Microsoft domain

The error does not by itself establish that the former Exchange/Outlook environment is responsible. Domain ownership should be investigated separately only if you need to recover or administer the old Microsoft tenant.

Check whether anyone still has administrator access to the former Microsoft 365 or Entra tenant. If the organization is locked out of an existing managed tenant, open a Microsoft Support case; Microsoft validates domain ownership and restores authorized Global Administrator access to the existing tenant.^5^

If investigation shows that memorialhealthcare.org belongs to an unmanaged/shadow Entra directory created through historical self-service signup, an internal administrator takeover is available. It requires creating a user context in that unmanaged directory, signing into the Microsoft 365 admin takeover flow, and proving domain ownership with a DNS TXT record.^6^ Do not start a takeover merely to open this OneDrive link; sender-side resharing through Entra B2B is the direct fix.

References

1. SharePoint and OneDrive integration with Microsoft Entra B2B
2. Email one-time passcode authentication for B2B guest users
3. Manage sharing settings for SharePoint and OneDrive in Microsoft 365
4. Unable to share OneDrive files | Microsoft Support
5. Plan for tenant recoverability
6. Take over an unmanaged directory as administrator in Microsoft Entra ID