An error occurred while attaching module (Dynamicweb.Frontend.Content)

System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
   at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
   at System.Collections.Generic.List`1.RemoveAt(Int32 index)
   at System.Collections.Generic.List`1.Remove(T item)
   at Dynamicweb.Ecommerce.Extensibility.Controls.ProductsHandler.GetProductCollectionFromDB()
   at Dynamicweb.Ecommerce.Orders.SalesDiscounts.SalesDiscount.GetSalesDiscountProvider()
   at Dynamicweb.Ecommerce.Orders.SalesDiscounts.SalesDiscountService.GetProductDiscounts(Language language)
   at Dynamicweb.Ecommerce.Discounts.DiscountCollection..ctor(Product product, Currency currency, Country country, String unitId, String shopId)
   at Dynamicweb.Ecommerce.Products.Product.GetDiscounts(Currency currency, Country country, String unitId, String shopId)
   at Dynamicweb.Ecommerce.Frontend.Renderer._Closure$__91-0._Lambda$__2()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderProduct(Product product, Boolean extendedProperties, Template template, Int32 loopCounter, Boolean renderRelated, String productUrl, Int32 quantity, Int32 wishListId, Boolean renderPublicList, Boolean isRecursiveCall, Lazy`1 categoryFieldSorting, Int32 orderLineOfProductCount, RenderingContext renderingContext, String unitId)
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderProduct(Product product, Boolean extendedProperties, String unitId)
   at Dynamicweb.Ecommerce.Frontend.Frontend.RenderProduct(Product product, String unitId)
   at Dynamicweb.Ecommerce.Frontend.Frontend.EcomRender()
   at Dynamicweb.Ecommerce.Frontend.Frontend.GetContent()
   at Dynamicweb.Frontend.Content.GetModuleOutput(Paragraph paragraph, PageView pageview)