I have (.res) File that contains some icons, I want to use these icons
with a n imagelist component ,

I have tried this but never success
 ImageList1.FileLoad(rtIcon,'c:\app\res\icons.res',0)
this function always returns false , any help will be very appreciated

Try this . I use this kind of thing all the time as the images "disappear"
when I deploy my project. So I put them in a res file and then load them
into the imagelist at startup.
______________________________________________________________________
var
   Bitmap1 : TBITMAP;
   Bitmap2 : TBITMAP;
   Bitmap3 : TBITMAP;
   Bitmap4 : TBITMAP;
begin
     Bitmap1 := TBitMap.Create;
     Bitmap2 := TBitmap.Create;
     Bitmap3 := TBitmap.Create;
     Bitmap4 := TBitmap.Create;
     Try
        Bitmap1.Handle := LoadBitmap(HInstance,'PAGE1');
        Bitmap2.Handle := LoadBitmap(HInstance,'PAGE2');
        Bitmap3.Handle := LoadBitmap(HInstance,'PAGE1');
        Bitmap4.Handle := LoadBitmap(HInstance,'PAGE2');
        Bitmap3.Mask(clPurple);
        Bitmap4.Mask(clPurple);

        ImageList1.Width := 24;
        ImageList1.Height := 24;
        ImageList1.Add(Bitmap1,Bitmap3);
        ImageList1.Add(Bitmap2,Bitmap4);
        PageControl1.ImageList := ImageList1;
     Finally
       Bitmap1.Free;
       Bitmap2.Free;
       Bitmap3.Free;
       Bitmap4.Free;
     end;