c# - C#:Emgu CV: Get error when try to get frame from capture device. AccessViolationException was unhandled

Question

private void CameraCapture_Load(object sender, EventArgs e)
 {
//Initialize the capture device
capture_face = new Capture();
capture_face.QueryFrame();
//Initialize the CapturedFrame event
Application.Idle += new EventHandler(CapturedFrame);
}

private void CapturedFrame(object sender, EventArgs e)
{            

current_Frame = capture_face.QueryFrame().Resize(400, 320, Emgu.CV.CvEnum.INTER.CV_INTER_CUBIC);

gray = current_Frame.Convert<Gray, Byte>();
}

AccessViolationException was unhandled. - Attempted to read or write protected memory.

Can anyone help on my issue?

I'm getting this error when I try to get the frame as current when I execute the form. I use windows 7.