@amjad.sahi, @Professionalize.Discourse, @John.He, @simon.zhao
worksheet.PageSetup.PaperSize = PaperSizeType.Custom;
// Set custom paper size for A1 (width: 33.1 inches, height: 23.4 inches)
worksheet.PageSetup.Custom…...path in server string fullPath = Path.Combine(Server.MapPath("~/App_Data")...