BCGControlBar Pro for MFC
void CBCGPMDIFrameWnd::RegisterAllMDIChildrenWithTaskbar ( BOOL  bRegister = TRUE)

Registers all MDI children with Windows 7 task bar in order to display their content in task bar thumbnails.

Call this function to register or unregister all MDI children with Windows 7 task bar in order to display their content in task bar thumbnails.

The application must use MDI Tabs or MDI Tabbed Groups.

Parameters
bRegisterSpecifies whether register (TRUE), or unregister MDI children.