The TaskBand class is registered by EXPLORER.EXE through the COM function CoRegisterClassObject when EXPLORER creates the desktop and taskbar. In ordinary practice then, almost all Windows programs can get an instance of this class created for them by using such well-documented COM functions as CoCreateInstance, treating EXPLORER as a local server, and giving the following CLSID:

CLSID_TaskBand {68284FAA-6A48-11D0-8C78-00C04FD918B4}

This CLSID is duplicated as the IID for the IInputObject interface, which appears to be the only way that Microsoft documents it.

The TaskBand class implements the following interfaces:

All of these are documented except IWinEventHandler (which has numerous implementations elsewhere).