The required anti-forgery form field "__RequestVerificationToken" is not present.

Dear All,
am trying our nopcommerce, am new to the development stuff :)
am facing the below error every time i try to rate the product any one can help.

Server Error in '/' Application.

The required anti-forgery form field "__RequestVerificationToken" is not present.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.Mvc.HttpAntiForgeryException: The required anti-forgery form field "__RequestVerificationToken" is not present.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[HttpAntiForgeryException (0x80004005): The required anti-forgery form field "__RequestVerificationToken" is not present.]
   System.Web.Helpers.AntiXsrf.TokenValidator.ValidateTokens(HttpContextBase httpContext, IIdentity identity, AntiForgeryToken sessionToken, AntiForgeryToken fieldToken) +678
   System.Web.Helpers.AntiXsrf.AntiForgeryWorker.Validate(HttpContextBase httpContext) +119
   System.Web.Mvc.ControllerActionInvoker.InvokeAuthorizationFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor) +157
   System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__19(AsyncCallback asyncCallback, Object asyncState) +1167
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +170
   System.Web.Mvc.Async.AsyncControllerActionInvoker.BeginInvokeAction(ControllerContext controllerContext, String actionName, AsyncCallback callback, Object state) +455
   System.Web.Mvc.Controller.<BeginExecuteCore>b__1c(AsyncCallback asyncCallback, Object asyncState, ExecuteCoreState innerState) +42
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallBeginDelegate(AsyncCallback callback, Object callbackState) +67
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +170
   System.Web.Mvc.Controller.BeginExecuteCore(AsyncCallback callback, Object state) +937
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +170
   System.Web.Mvc.Controller.BeginExecute(RequestContext requestContext, AsyncCallback callback, Object state) +711
   System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__4(AsyncCallback asyncCallback, Object asyncState, ProcessRequestState innerState) +94
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallBeginDelegate(AsyncCallback callback, Object callbackState) +67
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +170
   System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +555
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +923
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +157

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.6.1586.0