Hello All,

I worked with one of the customer to deploy Hybrid setup between exchange 2013 and office 365.

The customer have two Exchange 2013 servers multi-roles, and after we synchronized local Active directory with azure AD using AD Connect we tried to enable hybrid configuration wizard.

once we enabled hybrid configuration wizard we faced the error below:

Subtask CheckPrereqs execution failed: Check Tenant Prerequisites

Deserialization fails due to one SerializationException: 

Microsoft.Exchange.Compliance.Serialization.Formatters.BlockedTypeException: The type to be (de)serialized is not allowed: Microsoft.Exchange.Data.Directory.DirectoryBackendType

The customer have an exchange 2013 CU5, according to Microsoft article, this is a known error in this version of exchange and you should upgrade your exchange server to the latest cumulative update (CU), till the date of this article the latest CU is CU11, you can download it from here: https://www.microsoft.com/en-us/download/details.aspx?id=50366

After we upgraded the exchange servers, the hybrid configuration wizard worked and the error disappeared.

Reference for this know issue: https://support.microsoft.com/en-us/kb/2988229

About Blogger…

Ahmad Yasin (MCSA office 365, MCSE : Messaging, Azure Certified)

Ahmad Yasin in a Microsoft Cloud Engineer and the Owner & publisher of AzureDummies blog. He also hold many certificates in office 365 and windows azure including Developing Microsoft Azure Solutions, Implementing Microsoft Azure Infrastructure Solutions and MCSA office 365.
Ahmad is currently working in Specialized Technical Services Company (STS).