Required Field Doesn't work for one field but does for other

I am using a standard validation with MVC, acrossed with my fluent nHibernate

    [DisplayName("Product Name")]
    [Required(ErrorMessage = "Product Name Required")]
    public virtual string ProductName { get; set; }

    [DataType(DataType.MultilineText)]
    public virtual string Description { get; set; }

    [DataType(DataType.Currency)]
    [Required(ErrorMessage = "Price Required")]
    public virtual decimal Price { get; set; }

    [Required(ErrorMessage = "Quantity Required")]
    [Range(0, 100000, ErrorMessage = "Must be postive number less then 100000")]
    public virtual int Quantity { get; set; }


    public virtual bool Live { get; set; }

    public virtual ICollection<Attribute> Attribute { get; set; }
    public virtual ICollection<Images> Images { get; set; }

This is what makes up my "Product" class... for some reason the name doesnt validate as a required field but things like quantity and Price do.

View has these in it

<tr>
                <td>
                    <%= Html.LabelFor(model => model.ProductName)%>
                </td>
                <td>
                    <%= Html.TextBoxFor(model => model.ProductName, new { @class = "txt" })%>
                    <%= Html.ValidationMessageFor(model => model.ProductName)%>
                </td>
            </tr>

and this bit works fine

<tr>
                <td>
                    <%= Html.LabelFor(model => model.Pri开发者_如何学JAVAce) %>
                </td>
                <td>
                    <%= Html.TextBoxFor(model => model.Price, String.Format("{0:F}", Model.Price)) %>
                    <%= Html.ValidationMessageFor(model => model.Price) %>
                </td>
            </tr>

And this is the controller as asked for

    [AcceptVerbs(HttpVerbs.Post)]
    public ActionResult AddProduct(Product NewProduct)
    {
        if (ModelState.IsValid)
        {

            var ProductRepository = GetRepository<Product>();
            ProductRepository.Add(NewProduct);

            return Redirect("/");
        }

        return View(NewProduct);
    }

Just give it a try:

[DisplayName("Product Name")]
[Required(ErrorMessage = "Product Name Required", AllowEmptyStrings = false)]
public virtual string ProductName { get; set; }

i found that it was a isssue with not setting the data type

[DataType(DataType.Text)]

Was missing from my ProductName field!