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

System.Data.SqlClient.SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) ---> System.ComponentModel.Win32Exception (0x80004005): Access is denied
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   at System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.Open()
   at Dynamicweb.Data.DatabaseConnectionProvider.CreateConnection(Boolean open)
   at Dynamicweb.Data.Database.CreateConnection()
   at Dynamicweb.Data.Database.CreateDataReader(String sql, IDbConnection connection, IDbTransaction transaction, Int32 commandTimeout, Dictionary`2 sqlParams)
   at Dynamicweb.Ecommerce.Products.Period..ctor(String periodId)
   at Dynamicweb.Ecommerce.Products.Product.get_Period()
   at Dynamicweb.Ecommerce.Products.Product.get_IsActive()
   at Dynamicweb.Ecommerce.Products.ProductService.ReFactorProductList(ICollection`1 products, Currency currency, Country country, StockLocation stockLocation, User user, Boolean useAssortments)
   at Dynamicweb.Ecommerce.Products.ProductService.ReFactorProductList(ICollection`1 products, Boolean useAssortments)
   at Dynamicweb.Ecommerce.Products.ProductRepository.GetProductsBySql(CommandBuilder query, Boolean doRefactoring, Boolean bulkFill, Boolean useAssortments)
   at Dynamicweb.Ecommerce.Products.ProductRepository.GetAllProducts(String productLanguageId, Boolean useAssortments)
   at Dynamicweb.Ecommerce.Orders.Discounts.Discount.ProcessProductSelections(HashSet`1& productKeys, HashSet`1& includedQueries, HashSet`1& excludedQueries)
   at Dynamicweb.Ecommerce.Orders.Discounts.Discount.GetRelevantProductKeys()
   at Dynamicweb.Ecommerce.Orders.Discounts.DiscountService.StatelessSetLookup(Discount discount, ConcurrentDictionary`2 lookup)
   at Dynamicweb.Ecommerce.Orders.Discounts.DiscountService.InitializeLookup()
   at System.Lazy`1.CreateValue()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Lazy`1.get_Value()
   at Dynamicweb.Ecommerce.Orders.Discounts.DiscountService.GetDiscounts(DiscountApplyType[] discountTypes, String[] productKeys, Int32 userId, ICollection`1 groupIds, String customerNumber)
   at Dynamicweb.Ecommerce.Orders.Discounts.DiscountService.GetDiscounts(DiscountApplyType discountType, Product product, User user)
   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.EcomRender()
   at Dynamicweb.Ecommerce.Frontend.Frontend.GetContent()
   at Dynamicweb.Frontend.Content.GetModuleOutput(Paragraph paragraph, PageView pageview)
ClientConnectionId:29d1a4da-5469-4ed0-9961-c0861893a8c5
Error Number:5,State:0,Class:20