Задача на параллельную задачу.invoke()

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при выполнении первого цикла (i = 0)

System.InvalidOperationException: 'Invalid cross-thread operation: the 'boxframe' control was accessed from a different thread than the one from which the creation was performed.'

Что я уже пробовал:

private void CreaThumbs(string path)
{
 .....
            Action[] actions = new Action[3];     
            actions[0] = () => CreaBox(i);
            actions[1] = () => CreaImage(i, path, FileImg);
            actions[2] = () => CreaButton(i);

for (i = 0; i < elementi; i++)
  {
      ...........
      (Parallel.Invoke(actions);
      ..........
  }

private void CreaBox(int i)
        {
            boxCornice[i] = new Label();
	    ....
        }

private void CreaImmage(int i, string path, string NameFile)
        {
            //create PictureBox
            pictBox[i] = new PictureBox();
            pictBox[i].Parent = boxCornice[i];  //controllo associato            
            ........
	}            

private void CreaButton(int i)
        {
            btnRotateSx[i] = new PictureBox();
            btnRotateSx[i].Parent = boxCornice[i];
	    ....
	    btnRotateDx[i] = new PictureBox();
            btnRotateDx[i].Parent = boxCornice[i];
	    ....

        }
...
}

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