Entra B2B Guest Cannot Access Shared Resources

- Guest user receives access denied for shared site/team/file. - Invitation appears accepted but access still blocked. - Guest can access one workload but not another.

- Cross-tenant access settings conflict with guest policy. - Resource-level permissions are missing or inherited incorrectly. - Conditional Access for guests requires compliant controls not met.

Document whether the issue affects one user, multiple users, or multiple devices. Confirm exact error messages, recent changes (password reset, update, network change), and whether the same issue reproduces in web vs desktop workflows where applicable.

Confirm the user is signed in with the correct corporate account, system time is accurate, network/VPN connectivity is stable, and the application is not running in offline or limited mode.

Use the command snippets below to collect non-destructive diagnostics. Capture output in the ticket when escalation may be required. Avoid deleting profiles, cached credentials, or managed app data unless the runbook or admin approval explicitly allows it.

- Confirm guest object is active and mapped to the intended external identity. - Validate both tenant-level external collaboration policy and resource permissions. - Review guest sign-in logs for specific block reason and policy. - Coordinate with security before broadening guest access scope.