The Windows shell provides a powerful set of objects—the Shell object model—that lets you access all the main features of the OS's GUI. However, Shell objects aren't natively on all versions of Windows. The objects are a native part of the Windows 2000, Windows 98, and Windows Millennium Edition (Windows Me) OSs. To use the objects in a Windows NT 4.0 or Win95 system, you must install the Active Desktop Shell Update Release (ADSUR).

ADSUR is responsible for the colorful user interface (UI) that makes Windows Explorer look like the Microsoft Internet Explorer (IE) browser. That UI seems to have a bad reputation among NT Server 4.0 users. Nevertheless, if you want to use the objects, you must upgrade your system.

The only way you can install ADSUR is by installing IE 4.0 and selecting the Install Active Desktop option during setup. Curiously, IE 5.0 and later doesn't install ADSUR but simply upgrades ADSUR if it already exists. For more information, go to the Microsoft Developer Network (MSDN) Online Library at http://msdn.microsoft.com/library/default.asp?url=/library/psdk/shellcc/shell/versions.htm.