OAB (Offline Address Book), as you know, is one of the critical features of Microsoft Exchange Server. Microsoft Exchange Team has introduced a major change in architecture of OAB in Exchange Server 2013, mainly targeting to avoid the single point of failure of OAB generation process. As we all know, until Exchange 2010 when we create an Offline Address Book, we need to specify the mailbox server name that is responsible for the generation of OAB. Hence this server becomes a single point of failure thus affecting the generation process if the particular server becomes unavailable. In Exchange Server 2013, OAB generation does not owned by single server, whereas it generated by the Mailbox Server(s) that hosts special type of arbitration mailbox, called organization mailbox. Hence, the OAB generation is not bound to a single server. Exchange Component Responsible for OAB Generation, In all the previous versions of exchange Microsoft…