A new version of the Exchange 2013 MP has been released version 15.0.666.19 is available for download here.

Fixes in this version:

• Fixed a bug that was unable to run Exchange 2013 performance reports when the console is running on a locale different from EN-US.

Exception:
System.ArgumentNullException: Value cannot be null. Parameter name: GroupList

• Fixed a bug that was causing the collection of Synthetic mailbox performance count data to fail when there are more than 2 management servers. Event 102 is logged on the management servers with the below exception.

Exception:
System.Runtime.Serialization.SerializationException: Type ‘System.Object[]’ with data contract name ‘ArrayOfanyType:http://schemas.microsoft.com/2003/10/Serialization/Arrays’ is not expected.