In order to use the "invalid parameter" prompt to add ICO to the ImageList control, do not understand, and finally find actually to achieve the code, using the ICO class under the system.drawing namespace:
Systme.drawing.ico ico = new system.drawing.ico (path "of" ICO);
ImageList.images.Add (ICO);
Then specify that the control is used to use that ICO.
Why don't Microsoft do this Imagelist's wizard more better? Even if it is clear, it is good, otherwise, "Invalid parameters used", this prompt does not work at all.
