Search result Page throw Error for anonymous User

Question

We have claim base WebApplication in SharePoint 2013. Every thing is working fine and user can login site without any problem. Only search result page not working..its given "Sorry, something went wrong "
From ULS Log I found below exception
CoreResultsWebPart::OnInit: Exception initializing: System.InvalidOperationException: The security token request cannot be completed.    
 at Microsoft.SharePoint.SPSecurityContext.SecurityTokenForServiceContext(Uri contextUri)    
 at Microsoft.SharePoint.SPChannelFactoryOperations.InternalCreateChannelActingAsLoggedOnUser[TChannel](ChannelFactory`1 factory, EndpointAddress address, Uri via)    
 at Microsoft.Office.Server.Search.Administration.SearchServiceApplicationProxy.GetChannel(Uri address, Int32 timeoutInMilliseconds)    
 at Microsoft.Office.Server.Search.Administration.SearchServiceApplicationProxy.DoSpLoadBalancedUriWsOp[T](WebServiceBackedOperation`1 webServiceCall, Int32 timeoutInMilliseconds, Int32 wcfTimeoutInMilliseconds, String operationName)    
 at Microsoft.Office.Server.Search.Administration.SearchServiceApplicationProxy.DoWebServiceBackedOperation[T](String operationName, Int32 timeoutInMilliseconds, Int32 wcfTimeoutInMilliseconds, WebServiceBackedOperation`1 webServiceCall)    
 at Microsoft.Office.Server.Search.Administration.SearchServiceApplicationProxy.DoWebServiceBackedOperation[T](String operationName, WebServiceBackedOperation`1 webServiceCall)    
 at Microsoft.Office.Server.Search.Query.ConsumerScopeCache.Refresh(IEnumerable`1 sharedScopes)    
 at Microsoft.Office.Server.Search.Query.ConsumerScopeCache.EnsureFresh()    
 at Microsoft.Office.Server.Search.Query.ConsumerScopeCache.TryGetScope(Int32 id, ScopeInformation& scope)    
 at Microsoft.Office.Server.Search.Query.ScopeCache.TryGetScope(Guid siteGuid, Int32 id, ScopeInformation& scope)    
 at Microsoft.Office.Server.Search.WebControls.SearchCommon.GetScopeNameByScopeID(Guid siteGuid, Int32 scopeID)    
 at Microsoft.Office.Server.Search.WebControls.CoreResultsWebPart.SetPropertiesOnQueryReader()    
 at Microsoft.Office.Server.Search.WebControls.CoreResultsWebPart.OnInit(EventArgs e)
We are using Arabic Language Pack SharePoint 2013 on Windows server 2012 with SQL Server 2012.
 anonymous access already given form Central Admin and Sitecollection level 
Quick response will be highly Appreciated.

Answer 1

Its need to be set  impersonate="true"
<authentication mode="Forms">
    </authentication>
    <identity impersonate="true"
/>
to resolve custom solution which need impersonate="false"
Run command in evaluated privilege...