Exchange Powershell in Multi Domain Environment

This is quick one, if you're using Exchange PowerShell for managing environment where exchange recipients are located across multiple domains in forest, you might be wondering why by default you will not be able to manage recipient objects that are located in different domains. The reason for this behavior is that by default, you will be able to manage objects that are located in the domain where Exchange servers are located.
In order to change this behavior, for example to manage recipient objects located across forest Set-AdServerSettings cmdlet is your friend:

Set-AdServerSettings -ViewEntireForest $true

One thing to notice is that, the change of this view scope is only limited to current open session.