“Controller, Action, Model” not all code paths return a value

Question

I am really confused by this error "not all code paths return a value" on my action PostResponse. I have stared at my model, controller and view for hours and I think

Answer 1

try

   [HttpPost]
[ValidateAntiForgeryToken]
public ActionResult PostResponse([Bind(Include = "UserId,QuestionID,Answer,Source,Status,DateStamp")] Response response)
{
    if (ModelState.IsValid)
    {
        db.Responses.Add(response);
        db.SaveChanges();
    }
    else{
        return View("Error");
    }

}