Server Error in '/' Application.

Cannot insert the value NULL into column 'UserAgent', table 'VietnamDiscoveries.dbo.Sys_UserActivity'; column does not allow nulls. INSERT fails.
The statement has been terminated.

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.Data.SqlClient.SqlException: Cannot insert the value NULL into column 'UserAgent', table 'VietnamDiscoveries.dbo.Sys_UserActivity'; column does not allow nulls. INSERT fails.
The statement has been terminated.

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: 


[SqlException (0x80131904): Cannot insert the value NULL into column 'UserAgent', table 'VietnamDiscoveries.dbo.Sys_UserActivity'; column does not allow nulls. INSERT fails.
The statement has been terminated.]
   System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection) +1950890
   System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +4846875
   System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +194
   System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2392
   System.Data.SqlClient.SqlDataReader.ConsumeMetaData() +33
   System.Data.SqlClient.SqlDataReader.get_MetaData() +83
   System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString) +297
   System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async) +954
   System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result) +162
   System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method) +32
   System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method) +141
   System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior) +12
   System.Data.Common.DbCommand.ExecuteReader() +12
   System.Data.Linq.SqlClient.SqlProvider.Execute(Expression query, QueryInfo queryInfo, IObjectReaderFactory factory, Object[] parentArgs, Object[] userArgs, ICompiledSubQuery[] subQueries, Object lastResult) +975
   System.Data.Linq.SqlClient.SqlProvider.ExecuteAll(Expression query, QueryInfo[] queryInfos, IObjectReaderFactory factory, Object[] userArguments, ICompiledSubQuery[] subQueries) +113
   System.Data.Linq.SqlClient.SqlProvider.System.Data.Linq.Provider.IProvider.Execute(Expression query) +344
   System.Data.Linq.StandardChangeDirector.DynamicInsert(TrackedObject item) +136
   System.Data.Linq.StandardChangeDirector.Insert(TrackedObject item) +202
   System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode) +260
   System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode) +331
   FocusCo.Lib.Utls.Utl.SubmitDBChanges(DataContext db) in D:\Projects\FocusCo.Lib\Utls\Utl.cs:102

[Exception: Unhandled Exception]
   FocusCo.Lib.Utls.ExceptionUtl.HandleException(Exception ex, LogType type, T returnValue) in D:\Projects\FocusCo.Lib\Utls\ExceptionUtl.cs:23
   FocusCo.Lib.Utls.ExceptionUtl.HandleException(Exception ex, LogType type) in D:\Projects\FocusCo.Lib\Utls\ExceptionUtl.cs:49
   FocusCo.Lib.Utls.Utl.SubmitDBChanges(DataContext db) in D:\Projects\FocusCo.Lib\Utls\Utl.cs:109
   WebMonitorHelper.UpdateRequestHistory(HttpApplication app) in D:\Projects\FocusCo.Lib\WebCounter.cs:271
   VietNamDiscoveries.Models.WebLogAttribute.OnActionExecuting(ActionExecutingContext filterContext) in D:\Projects\Vietnamdiscoveries\trunk\Helper\Attribute.cs:96
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +47
   System.Web.Mvc.<>c__DisplayClassf.<InvokeActionMethodWithFilters>b__c() +19
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +254
   System.Web.Mvc.<>c__DisplayClassf.<InvokeActionMethodWithFilters>b__c() +19
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +254
   System.Web.Mvc.<>c__DisplayClassf.<InvokeActionMethodWithFilters>b__c() +19
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +192
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +314
   System.Web.Mvc.Controller.ExecuteCore() +105
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +39
   System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +7
   System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__4() +34
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +21
   System.Web.Mvc.Async.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _) +12
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +59
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +44
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +7
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +8690990
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Version Information: Microsoft .NET Framework Version:2.0.50727.3634; ASP.NET Version:2.0.50727.3634