I am getting this error when trying to run the solution. This happens just after I enter username password

Server stack trace:
   at System.ServiceModel.Security.IssuanceTokenProviderBase`1.DoNegotiation(TimeSpan timeout)
   at System.ServiceModel.Security.SspiNegotiationTokenProvider.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Security.TlsnegoTokenProvider.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Security.WrapperSecurityCommunicationObject.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Security.CommunicationObjectSecurityTokenProvider.Open(TimeSpan timeout)
   at System.ServiceModel.Security.SymmetricSecurityProtocol.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Security.WrapperSecurityCommunicationObject.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.SecurityChannelFactory`1.ClientSecurityChannel`1.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Security.SecuritySessionSecurityTokenProvider.DoOperation(SecuritySessionOperation operation, EndpointAddress target, Uri via, SecurityToken currentToken, TimeSpan timeout)
   at System.ServiceModel.Security.SecuritySessionSecurityTokenProvider.GetTokenCore(TimeSpan timeout)
   at System.IdentityModel.Selectors.SecurityTokenProvider.GetToken(TimeSpan timeout)
   at System.ServiceModel.Security.SecuritySessionClientSettings`1.ClientSecuritySessionChannel.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.CallOpenOnce.System.ServiceModel.Channels.ServiceChannel.ICallOnce.Call(ServiceChannel channel, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(TimeSpan timeout, CallOnceManager cascade)
   at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
   at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)

Exception rethrown at [0]:
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at EAppointments.UI.ServiceAgents.AppointmentService.IAppointmentService.Find(AppointmentSearchCriteria criteria)
   at EAppointments.UI.ServiceAgents.AppointmentService.AppointmentServiceClient.Find(AppointmentSearchCriteria criteria) in C:\Temp\Software\AssetScheduler\E-Appointments 1.1\E-Appointments 1.1\Solution\UI\Common\EAppointments.UI.ServiceAgents\Service References\AppointmentService.cs:line 1580
   at EAppointments.UI.ServiceAgents.AppointmentServiceAgent.Find(AppointmentSearchCriteria criteria) in C:\Temp\Software\AssetScheduler\E-Appointments 1.1\E-Appointments 1.1\Solution\UI\Common\EAppointments.UI.ServiceAgents\AppointmentServiceAgent.cs:line 42
   at EAppointments.UI.Modules.AppointmentController.Find(Nullable`1 patientId, Nullable`1 startDateTime, Nullable`1 endDateTime, Int32 status) in C:\Temp\Software\AssetScheduler\E-Appointments 1.1\E-Appointments 1.1\Solution\UI\Common\EAppointments.UI.Modules\Appointments\AppointmentController.cs:line 58
   at EAppointments.UI.Modules.Views.AppointmentListViewPresenter.OnViewLoaded() in C:\Temp\Software\AssetScheduler\E-Appointments 1.1\E-Appointments 1.1\Solution\UI\Common\EAppointments.UI.Modules\Appointments\Views\AppointmentListViewPresenter.cs:line 37
   at Appointment_List.BindData() in c:\Temp\Software\AssetScheduler\E-Appointments 1.1\E-Appointments 1.1\Solution\UI\Web\EAppointmentsWeb\Appointment\Controls\List.ascx.cs:line 100
   at Appointment_List.Page_Load(Object sender, EventArgs e) in c:\Temp\Software\AssetScheduler\E-Appointments 1.1\E-Appointments 1.1\Solution\UI\Web\EAppointmentsWeb\Appointment\Controls\List.ascx.cs:line 50
   at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e)
   at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
   at System.Web.UI.Control.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)