System.NullReferenceException: Object reference not set to an instance of an object.
   at Smartpage.Nav.MainItem.Providers.ProductProvider.<>c__DisplayClassf.<>c__DisplayClass18.b__b(Product p) in c:\Workspace\55 nord\Main\Source\55Nord.MainItem\Providers\ProductProvider.cs:line 139
   at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate)
   at Smartpage.Nav.MainItem.Providers.ProductProvider.<>c__DisplayClassf.b__a(ProductMainItems cp) in c:\Workspace\55 nord\Main\Source\55Nord.MainItem\Providers\ProductProvider.cs:line 139
   at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at Smartpage.Nav.MainItem.Providers.ProductProvider.GetProductMainItems(ICollection`1 products) in c:\Workspace\55 nord\Main\Source\55Nord.MainItem\Providers\ProductProvider.cs:line 139
   at Smartpage.Nav.MainItem.Providers.ProductProvider.GetProductMainItems(Product product) in c:\Workspace\55 nord\Main\Source\55Nord.MainItem\Providers\ProductProvider.cs:line 56
   at Smartpage.Nav.MainItem.TemplateExtenders.ProductTemplateExtender.ExtendTemplate(Template template) in c:\Workspace\55 nord\Main\Source\55Nord.MainItem\TemplateExtenders\ProductTemplateExtender.cs:line 13
   at Dynamicweb.eCommerce.Frontend.Renderer.RenderProductTemplateExtenders(Product Product, Template Template, Boolean ExtendedProperties)
   at Dynamicweb.eCommerce.Frontend.Renderer.RenderProduct(Product Product, Boolean ExtendedProperties, Template Template, Int32 loopCounter, Boolean renderRelated, String productURL, Int32 quantity, Int32 wishListID, Boolean renderPublicList, Int32 orderLineOfProductCount)
   at Dynamicweb.eCommerce.Frontend.Renderer.RenderProduct(Product Product, Boolean ExtendedProperties)
   at Dynamicweb.eCommerce.Frontend.Frontend.EcomRender()
   at Dynamicweb.eCommerce.Frontend.Frontend.GetContent()
   at Dynamicweb.Frontend.Content.GetModule(DataRow& ParagraphRow)