This feature is only available in Enterprise Edition.
If enabled, the When searching "My Computer", include mapped network drives setting will allow Identity Finder to search any drive letter that is mapped to a drive on another computer. Identity Finder will search every drive letter you can see within Windows explorer. By disabling this feature, Identity Finder will only search physical drives, including removable drives.
To view or change these settings, click the Settings button on the Tools and Options ribbon.