Answered
my child clip does not support property
I have "myStage" movie clip on my scene1>layer 1>Frame and go is child movieclip of myStage. Default I want to hide "go" movieclip. But my code does not work any more. What was the error on my code.
Code on : scene1>Layer 1 > Frame 1
root.myStage.go.visible=false;