Internet Information Server (IIS) is built into Windows Server 2000. How do you install Windows Server 2000 from Windows 2000 Pro?
Unfortunately, Microsoft doesn't provide a way to upgrade from Windows 2000 Professional to Windows 2000 Server. If you need the Windows 2000 Server version of IIS, your best option is to perform a clean install of Windows 2000 Server and re-install any applications you need. Windows 2000 Professional does include IIS 5.0, though, and that may fit your needs if you don't need any server-specific features.
This was first published in March 2001