- You deploy more than one front-end pool, such as pool A and pool B, in a Microsoft Lync Server 2013 environment.
- You deploy Microsoft Exchange Server 2010.
- You integrate Lync Server 2013 instant messaging with Exchange Server 2010 Outlook Web App (OWA).
- You associate Exchange Server 2010 with pool A.
- A user (user A) is homed in pool A, and another user (user B) is homed in pool B.
- User A and user B sign in to OWA separately.