Excel found unreadable content in

Apr 6, 2012 at 4:08 AM
Edited Apr 6, 2012 at 4:09 AM
               string picturePath = Server.MapPath("~/Styles/Images/111.jpg");
                System.Drawing.Bitmap picture = new System.Drawing.Bitmap(picturePath);
                picture.SetResolution(96.0F, 96.0F);
                ExcelPicture pictureLogo = sheet.Drawings.AddPicture("pictureLogo", picture);

                pictureLogo.SetSize(38);
                pictureLogo.SetPosition(1, -65, 14, -235);

when I export excel then modify other cell fomart.save the excel then open it.it will show
Excel found unreadable content in ....when I click 'yes'.the picture and sharp will lost all.