The Exchange management tools are implemented as an extension, or snapin, of Microsoft PowerShell. Currently only PowerShell version 1.0 is supported and needs to be installed on the server:
The PowerShell environment logs messages to the event viewer. There are two event logs created for PowerShell in a standard installation: the “PowerShell” and “Windows PowerShell” event logs. The “PowerShell” event log is used when the gateway creates a PowerShell runtime environment. When a write operation fails to write to the event log, the PowerShell environment will not start up, and all PowerShell-related actions of the gateway will fail. To prevent this failure, you should monitor and clean up the event log regularly or configure it to overwrite messages.