Simulating Ctrl+Alt+Delete

Question

I wish to simulate Ctrl+Alt+Delete.

From looking at the vnc source code, I see that thread has to be on desktop "Winlogon", so then when I call OpenDesktop "Winlogon" on Vista, I get return value of 0.

OpenDesktop("Winlogon", 0, false, DESKTOP_CREATEMENU | DESKTOP_CREATEWINDOW | DESKTOP_ENUMERATE | DESKTOP_HOOKCONTROL | DESKTOP_WRITEOBJECTS | DESKTOP_READOBJECTS | DESKTOP_SWITCHDESKTOP | GENERIC_WRITE);

Any one know how can I access the winlogon desktop?

Thank you