DirectShow Ctrl+Alt+del error in Win2000

I am using IVideoWindow interface to display live image from external analog signal.
When I press Ctrl+Alt+Del in Windows2000 then live imagedisappears and all i see is black image.

If it happed I can only rebuild the filtergraph again.
FilterGraph.Active:= false;
FilterGraph.ClearGraph();
FilterGraph.Active = true;
ConnectPreviewGraph();
Play();

Can anybody please explain this behavior in Windows2000?

[499 byte] By [Pigotka] at [2007-12-28]

Software Development for Windows Vista

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