The Get-LogonStatistics cmdlet is used to retrieve logon statistics about currently active sessions such as user name, logon time, last access time and client version for example.
As you can see from the next screenshot, the Get-LogonStatistics cmdlet is still present in Exchange 2013 all the way to the latest CU5:
However, if you actually try to use it, you will get an error similar to the following:
The specified mailbox "DB01" doesn't exist.
+ CategoryInfo : NotSpecified: (:) [Get-LogonStatistics], ManagementObjectNotFoundException + FullyQualifiedErrorId : [Server=EXAIO,RequestId=361f29b3-6474-4aad-a43e-111fe3af86b2,TimeStamp=07/08/2014 14:42:08] [FailureCategory=Cmdlet-ManagementObjectNotFoundException] 83C28CB1,Microsoft.Exchange.Management.MapiTasks.GetLogonStatistics
Cannot find LogonStatistics objects from the root 'DB01'. Please make sure that you specified the correct search root and that you have the correct permissions to perform the search.
+ CategoryInfo : NotSpecified: (:) [Get-LogonStatistics], MapiOperationException
+ FullyQualifiedErrorId : [Server=EXAIO,RequestId=ebda72ad-ce19-443e-95bf-6b417cd14d7e,TimeStamp=07/08/2014 14:42:18] [FailureCategory=Cmdlet-MapiOperationException] 3962F04B,Microsoft.Exchange.Management.MapiTasks.GetLogonStatistics
The reason for this error is that this cmdlet has been deprecated in Exchange 2013 since RTM! According to Microsoft, “Get-LogonStatistics is no longer supported by Exchange 2013. The cmdlet and documentation will eventually be removed.”
The documentation mentioned above refers to a couple of TechNet articles that still mentioned the cmdlet. However, these now seem to have been removed.