Assume that Microsoft Exchange Server 2013 is deployed in a domain that has a disjoint namespace. After you apply Service Pack 1 (SP1) for Exchange Server 2013, you receive the following error message when you manage a Database Availability Group (DAG) in Exchange Admin Center:
Some or all identity references could not be translated.
WARNING: An unexpected error has occurred and a Watson dump is being generated: Some or all identity references could not be translated. Some or all identity references could not be translated. + CategoryInfo : NotSpecified: (:) [Set-DatabaseAvailabilityGroup], IdentityNotMappedException + FullyQualifiedErrorId : System.Security.Principal.IdentityNotMappedException,Microsoft.Exchange.Management.Syste mConfigurationTasks.SetDatabaseAvailabilityGroup
About disjoint namespace In most domain topologies, the primary DNS suffix of the computers in the domain is the same as the DNS domain name. In some cases, you may require these namespaces to be different. This is known as a disjoint namespace.
This issue occurs after you apply Exchange Server 2013 SP1.
To resolve this issue, install the following update:
2936880 Cumulative Update 5 for Exchange Server 2013