how do you set the old .left and .top properties so that the control moves to where you tell it?

i've tried the following two methods and neither work. all i want is for the combo box to appear where the mouse is.

Code:
            Dim p As Point
            p.X = Cursor.Position.X
            p.Y = Cursor.Position.Y
            ComboBox.PointToScreen(p)
Code:
            ComboBox.Left = Cursor.Position.X
            ComboBox.Top = Cursor.Position.Y