B2B Direct Connect and File Sharing Support

Microsoft Support Team,

We are configuring Microsoft Entra B2B Direct Connect between three separate Microsoft 365 tenants:

• NorthstarTech.example

BluePeakSystems.example

CedarBridgeGroup.example

Each organization has its own tenant and native user accounts. For example:

[Moderator note: Personally Identifiable Information removed]  @northstartech.example

[Moderator note: Personally Identifiable Information removed]  @bluepeaksystems.example

[Moderator note: Personally Identifiable Information removed]  @cedarbridgegroup.example

These are separate native accounts, and we want to maintain them in their respective home tenants.

Primary Requirement

Our objective is to use Microsoft Entra B2B Direct Connect while maintaining each user's existing identity in their home tenant and avoiding the creation of additional Guest accounts.

We want to understand the capabilities and limitations of B2B Direct Connect when used with Microsoft Teams, particularly regarding one-to-one chats, domain trust recognition, and file sharing.

Current Issues

1. Teams one-to-one chat trust recognition

When initiating one-to-one Teams chats between users from our separate tenants, we want the domains to be recognized as trusted.

Currently, Teams displays a message indicating that the domain is not on the trusted domains list.

We would like to understand how Microsoft Entra B2B Direct Connect and Teams can recognize these organizations as trusted without requiring us to manually add each domain to the trusted domains list in the Teams Admin Center.

Our goal is to determine whether the existing cross-tenant access configuration can provide the necessary trust recognition, or whether the Teams external access domain allowlist must also be configured.

2. Teams chat file sharing

After configuring B2B Direct Connect, we encountered an issue with file sharing in Microsoft Teams chats.

When communicating with users from a trusted tenant, drag-and-drop file sharing does not work as expected.

We would like Microsoft to clarify whether this behavior is expected with B2B Direct Connect or whether additional configuration is required.

Questions for Microsoft Support

1. B2B Direct Connect and file sharing

Does Microsoft Entra B2B Direct Connect support file sharing in Microsoft Teams chats, including drag-and-drop functionality?

2. One-to-one chat and trusted domain recognition

How can we configure Teams so that one-to-one chats recognize our domains as trusted instead of displaying the message that the domain is not on the trusted domains list?

Can this be achieved through Microsoft Entra cross-tenant access settings and B2B Direct Connect without manually adding each domain to the Teams Admin Center trusted domains list?

3. Required configuration

Are additional settings required in any of the following services to enable the expected functionality?

Microsoft Entra ID and cross-tenant access settings.

Microsoft Teams external access.

Teams Admin Center domain restrictions.

SharePoint and OneDrive sharing settings.

B2B Direct Connect configuration.

4. Domain trust and tenant relationships

Can Microsoft Teams automatically recognize an organization as trusted based on the existing B2B Direct Connect relationship, or is the Teams external access domain allowlist managed independently?

If these configurations are independent, what is the recommended approach to avoid maintaining duplicate domain allowlists where possible?

5. Guest-free configuration

Can these capabilities be enabled while keeping users as native accounts in their respective tenants and avoiding the creation of Guest accounts?

6. Product limitations and recommended approach

If trusted domain recognition or drag-and-drop file sharing is not supported through B2B Direct Connect alone, please confirm the applicable product limitations and recommend the Microsoft-supported configuration that best meets our requirements.

Important Requirements

Our requirements are:

Maintain separate native user accounts in each tenant.

Avoid creating additional Guest identities.

Enable one-to-one Teams chats between users in the separate tenants.

Understand how to achieve trusted domain recognition without manually maintaining the Teams Admin Center trusted domains list, if supported.

Enable file sharing in Teams chats, including drag-and-drop functionality.

We would appreciate Microsoft's guidance on the supported capabilities, the relationship between B2B Direct Connect and Teams external access domain restrictions, and the exact configuration required to achieve the expected behavior.

Thank you for your assistance.