Unable to share Loop Workspace for another member

Hello @Chau Pham

As you described, you've run into a classic "ghost invitation" issue. It’s confusing when the UI tells you everything is fine, but the backend doesn't seem to get the memo.

In this case, you can try to re-add your friend or ask your friend to add you to their workspace to see if this issue still persists.

Besides, you can try sending the invite from a private/incognito browser window. This method can help you bypass potential browser cache issues or conflicting extensions that might be interfering with the invitation process.

https://loop.cloud.microsoft/

If you still need my assistance, please come back with screenshots or any additional details so I can review it again and see if there’s anything more I can help you with.  

Have a nice day!  

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The behavior is consistent with current limitations and configuration requirements for sharing Loop workspaces, especially when external or guest users are involved.

Key points and checks:

1. External/guest sharing support
   • Loop workspaces and pages can be shared with external users (guests) only if the organization allows it and the required conditions are met.
   • If the friend is outside the organization and guest/external sharing is not fully enabled or configured, workspace invitations will silently fail or not complete correctly, which matches the symptoms (no email, user not added to member list).
2. Requirements for sharing Loop workspaces with guests The following must be true in the tenant that owns the Loop workspace:
   1. Organization-level external sharing must be enabled. See: manage the organization-level external sharing setting for SharePoint/OneDrive.
   2. The guest must either:
      • Already have a guest account in the tenant, or
      • Be invited via Business-to-Business (B2B) Invitation Manager so a guest account can be created.
   3. Sensitivity labels and conditional access must not block external sharing for Loop containers.
   4. External sharing for Loop (SharePoint Embedded containers of type = Loop) must not be disabled via the application external sharing override.
   If any of these are blocked or misconfigured, the workspace invitation will not complete, even though the UI may briefly indicate success.
3. Why sharing a single page link works
   • Sharing an individual Loop page or component via a direct “Share with specific people” link can succeed even when workspace-level membership is restricted, because the sharing flow may create or use a guest account just for that item.
   • This explains why the “Idea page” link works, while adding the friend as a workspace member does not.
4. Actions to resolve Because these are tenant-level settings, resolution requires the Microsoft 365 administrator of the tenant that owns the Loop workspace:
   1. Verify external/guest sharing is allowed
      • In SharePoint/OneDrive admin, confirm organization-level external sharing is enabled at a level that permits sharing with guests.
   2. Ensure the friend has a valid guest account
      • In Microsoft Entra ID (Azure AD), confirm the friend’s email exists as a Guest user.
      • If not, have the admin explicitly invite the friend as a guest and ensure the invitation is accepted.
   3. Check sensitivity labels and conditional access
      • Confirm no sensitivity label applied to the Loop workspace/container is blocking external sharing.
      • Confirm conditional access policies are not preventing the guest from being added as a workspace member.
   4. Check the Loop application external sharing override
      • If the admin has configured an application external sharing override for the Loop OwningApplicationID a187e399-0c36-4b98-8f04-1edc167a0996, verify it is not set to block external sharing for Loop containers.

If the friend is internal (same organization) and this still occurs, the admin should still review the above controls (especially sensitivity labels and any overrides) and verify that Loop workspace membership is not being restricted by policy.

Until the tenant configuration is corrected, continue using direct page links as a workaround for collaboration with that user.

References:

• Overview of Loop workspaces and Loop components permissions
• Get started with Microsoft Loop
• Use Loop components in Word for the web