Each Mailbox server hosts virtual directories in IIS that support OWA, Exchange Control Panel (ECP), ActiveSync, Offline Address Book (OAB), and Exchange Web Services (EWS). Each of these services has an associated cmdlet set that can be used to manage the settings of each virtual directory. One of the most common configuration changes made during the deployment process is modifying the internal and external URLs for each of these services. The required configuration varies greatly depending on a number of factors in your environment, especially in larger, multi-site environments.
The following cmdlets can be used to modify several settings for each virtual directory, including the values for the internal and external URLs: ...