public ActionResult AddInstrument(Instrument instrument) { if (_dashboardSP.CheckDuplicate <Instrument>(instrument.InstrumentName, instrument.Website)) { TempData["CustomError"] = "Instrument ( " + instrument.InstrumentName + " ) already exists!"; ModelState.AddModelError("CustomError", "Instrument ( " + instrument.InstrumentName + " ) already exists!"); } if (ModelState.IsValid) { _dashboardSP.Add(instrument); return(RedirectToAction("Index")); } return(RedirectToAction("AddInstrument")); }