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

System.NullReferenceException: Object reference not set to an instance of an object.
   at Dynamicweb.Rendering.Template.GetLoop(String name)
   at Co3.MCH.Mh.Dw.Extenders.ProductExtender.RenderTemplateTags() in C:\Data\Development\git\mch-messehaandbog-solution\Co3.MCH.Mh.Dynamicweb\Extenders\ProductExtender.cs:line 105
   at Co3.MCH.Mh.Dw.Extenders.ProductExtender.ExtendTemplate(Template template, ProductTemplateExtender extender, CacheEngine cacheEngine) in C:\Data\Development\git\mch-messehaandbog-solution\Co3.MCH.Mh.Dynamicweb\Extenders\ProductExtender.cs:line 69
   at Co3.Espresso.Dw8.Extenders.ProductExtender.ExtendTemplate(Template template) in c:\Data\Development\git\co3-espresso-solution.git\Co3.Espresso.Dynamicweb8\Extenders\ProductExtender.cs:line 107
   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)