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

System.Reflection.ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
   at System.Reflection.RuntimeModule.GetTypes(RuntimeModule module)
   at System.Reflection.Assembly.GetTypes()
   at System.Linq.Enumerable.d__17`2.MoveNext()
   at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()
   at Dynamicweb.Indexing.Lucene.Analyzers.AnalyzerFactory.LoadCreators()
   at Dynamicweb.Indexing.Lucene.Analyzers.AnalyzerFactory.get_Instance()
   at Dynamicweb.Indexing.Lucene.Helpers.GetAnalyzer(IIndex index, String providerTypeName)
   at Dynamicweb.Indexing.Lucene.Helpers.ParseQueryExpression(IIndex index, Expression expression, QuerySettings settings)
   at Dynamicweb.Indexing.Lucene.LuceneIndexProvider.SearchInternal(IQuery query, QuerySettings settings)
   at Dynamicweb.Indexing.Querying.QueryService.Query(IQuery query, QuerySettings settings)
   at Dynamicweb.Ecommerce.Indexing.ProductQueryHelper.ExecuteQuery(IQuery query, QuerySettings settings, PageView pageview)
   at Dynamicweb.Ecommerce.Indexing.ProductQueryHelper.GetProductsAutoIdsFromIndexQuery(IQuery query, QuerySettings querySettings, PageView pageview, Boolean showFacetOptionsWithNoResults, IEnumerable`1& facetViewModel, IEnumerable`1& spellCheckerResult, Int32& totalProductCount)
   at Dynamicweb.Ecommerce.Indexing.ProductQueryHelper.GetProductsAutoIds(ProductCatalogSettings settings, String groupId, ContentModule contentModule, PageView pageview, IEnumerable`1& facetViewModel, IEnumerable`1& spellCheckerResult)
   at Dynamicweb.Ecommerce.ProductCatalog.ProductCatalogFrontend.RenderProductList(ProductCatalogSettings settings, String groupId, Boolean feed)
   at Dynamicweb.Ecommerce.ProductCatalog.ProductCatalogFrontend.GetContent()
   at Dynamicweb.Frontend.Content.GetModuleOutput(Paragraph paragraph, PageView pageview)