CRM 2011 Security settings for this service require Windows Authentication but it is not enabled for the IIS application that hosts this service

When trying to connect to org through Plugin registration tool, was getting error.

When tried to browse http://server:5555/XRMServices/2011/Discovery.svc also was getting error and detail of error is in event viewer as 

WebHost failed to process a request.
Sender Information: System.ServiceModel.Activation.HostedHttpRequestAsyncResult/65652305
Exception: System.ServiceModel.ServiceActivationException: The service '/xrmservices/2011/Discovery.svc' cannot be activated due to an exception during compilation. The exception message is: Security settings for this service require Windows Authentication but it is not enabled for the IIS application that hosts this service.. ---> System.NotSupportedException: Security settings for this service require Windows Authentication but it is not enabled for the IIS application that hosts this service.
at System.ServiceModel.Activation.HostedAspNetEnvironment.ValidateHttpSettings(String virtualPath, Boolean isMetadataListener, Boolean usingDefaultSpnList, AuthenticationSchemes& supportedSchemes, ExtendedProtectionPolicy& extendedProtectionPolicy, String& realm)
at System.ServiceModel.Channels.HttpChannelListener.ApplyHostedContext(String virtualPath, Boolean isMetadataListener)
at System.ServiceModel.Channels.HttpTransportBindingElement.BuildChannelListener[TChannel](BindingContext context)
at System.ServiceModel.Channels.Binding.BuildChannelListener[TChannel](Uri listenUriBaseAddress, String listenUriRelativeAddress, ListenUriMode listenUriMode, BindingParameterCollection parameters)
at System.ServiceModel.Description.DispatcherBuilder.MaybeCreateListener(Boolean actuallyCreate, Type[] supportedChannels, Binding binding, BindingParameterCollection parameters, Uri listenUriBaseAddress, String listenUriRelativeAddress, ListenUriMode listenUriMode, ServiceThrottle throttle, IChannelListener& result, Boolean supportContextSession)
at System.ServiceModel.Description.DispatcherBuilder.BuildChannelListener(StuffPerListenUriInfo stuff, ServiceHostBase serviceHost, Uri listenUri, ListenUriMode listenUriMode, Boolean supportContextSession, IChannelListener& result)
at System.ServiceModel.Description.DispatcherBuilder.InitializeServiceHost(ServiceDescription description, ServiceHostBase serviceHost)
at System.ServiceModel.ServiceHostBase.InitializeRuntime()
at System.ServiceModel.ServiceHostBase.OnOpen(TimeSpan timeout)
at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(String normalizedVirtualPath)
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath)
--- End of inner exception stack trace ---
at System.Runtime.AsyncResult.End[TAsyncResult](IAsyncResult result)
at System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result)
Process Name: w3wp
Process ID: 3648

--

When opened IIS manager Microsoft Dynamic CRM authentication was set to "Windows Authentication" but was still getting above error.

Resolution:

This was due to mistakenly someone removed "Negotiate" Provider from "Microsoft Dynamic CRM" website,

To add it back perform following steps

Start->Run-> Inetmgr -> Microsoft Dynamic CRM -> select authenticate and click open feature in action panel ->click windows authentication and click on providers in action panel-> select Negotiate from available providers dropdown list and click add, and move it to top.

Restart IIS