One of the key features of Directory Opus is its Explorer Replacement mode. To clarify exactly what we mean by Explorer replacement:
whenever an action is taken that would ordinarily result in an Explorer window opening, a Directory Opus window (Lister) will open instead.
That's to say, Opus does not replace the desktop (which is actually implemented by explorer.exe), nor does it replace the standard File Open / Save dialogs in other applications.
Explorer replacement mode is controlled by the options on the Launching Opus / Explorer Replacement Preferences page. Selecting any option other than Don't replace Explorer activates Explorer replacement mode.
When Explorer replacement mode is enabled, it is still possible to get to Explorer if desired:
Please note that even when Explorer replacement mode is enabled, there are some cases when Explorer will continue to open:
In Vista and Windows 7, Opus will never open the Control Panel (or its various sub-pages) - they will always open in Explorer.
Explorer replacement mode is unavailable when running a USB exported version of Directory Opus.