Hi, there appears to be a bug when using the "add to cart" from the categories page.
In this case we are using nop for a donation site www.cycle4cancer.co.nz. We started with 1.8 (first time we have used 1.8 or 1.9) and have just moved to 1.9 however both versions appear to have the same issue.
When using nop for donations, shipping is disabled within the product pages and we disabled all of the shipping methods.
We think this is the process to generate the problem. When you "add to cart" from the categories page the browser goes to the error page or to the cart and doesn't add the product to the cart, the product in this case being a donation. The error log showed the ERROR below. It appears by ticking Free shipping over 'X' and entering $1 fixed the error problem below.
The "add to cart" from cat list problem is still there. "Add to cart" from the category, the item wont add to the cart. The cart opens but there is no item. If you then go into the details for the product then add to cart it will add to the cart. If you then clear the cart, close the browser and restart you can now "add to cart" from the categories list. It appears that once the cart has has initially received a product then problem is solved
---------------ERROR--------
System.Web.HttpUnhandledException (0x80004005): Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> NopSolutions.NopCommerce.Common.NopException: Shipping rate computation method could not be loaded at NopSolutions.NopCommerce.BusinessLogic.Shipping.ShippingService.GetShoppingCartShippingTotal(ShoppingCart cart, Customer customer, Boolean includingTax, Decimal& taxRate, Discount& appliedDiscount, String& error) at NopSolutions.NopCommerce.BusinessLogic.Shipping.ShippingService.GetShoppingCartShippingTotal(ShoppingCart cart, Customer customer, Boolean includingTax, Decimal& taxRate, String& error) at NopSolutions.NopCommerce.BusinessLogic.Shipping.ShippingService.GetShoppingCartShippingTotal(ShoppingCart cart, Customer customer, Boolean includingTax, String& error) at NopSolutions.NopCommerce.BusinessLogic.Shipping.ShippingService.GetShoppingCartShippingTotal(ShoppingCart cart, Customer customer, String& error) at NopSolutions.NopCommerce.BusinessLogic.Shipping.ShippingService.GetShoppingCartShippingTotal(ShoppingCart cart, Customer customer) at NopSolutions.NopCommerce.Web.Modules.OrderTotalsControl.BindData(Boolean isShoppingCart) at NopSolutions.NopCommerce.Web.Modules.OrderSummaryControl.BindData() at NopSolutions.NopCommerce.Web.Modules.OrderSummaryControl.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.HandleError(Exception e) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.ProcessRequest() at System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) at System.Web.UI.Page.ProcessRequest(HttpContext context) at ASP.shoppingcart_aspx.ProcessRequest(HttpContext context) at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
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