[SecurityException: 不允许所请求的注册表访问权。]
   Microsoft.Win32.RegistryKey.OpenSubKey(String name, Boolean writable) +473
   System.Diagnostics.EventLog.FindSourceRegistration(String source, String machineName, Boolean readOnly) +295
   System.Diagnostics.EventLog.SourceExists(String source, String machineName) +77
   System.Diagnostics.EventLog.WriteEntry(String message, EventLogEntryType type, Int32 eventID, Int16 category, Byte[] rawData) +178
   System.Diagnostics.EventLog.WriteEntry(String source, String message, EventLogEntryType type, Int32 eventID, Int16 category, Byte[] rawData) +68
   System.Diagnostics.EventLog.WriteEntry(String source, String message, EventLogEntryType type, Int32 eventID, Int16 category) +21
   System.Diagnostics.EventLog.WriteEntry(String source, String message, EventLogEntryType type, Int32 eventID) +15
   System.Diagnostics.EventLog.WriteEntry(String source, String message, EventLogEntryType type) +11
   Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionUtility.LogHandlingException(String policyName, Exception offendingException, Exception chainException, Exception originalException)
   Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionPolicyEntry.ExecuteHandlerChain(Exception ex, Guid handlingInstanceID)
   Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionPolicyEntry.Handle(Exception ex)
   Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionPolicy.HandleException(Exception ex)
   Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionPolicy.HandleException(Exception ex, String policyName, ConfigurationContext configurationContext)
   Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionPolicy.HandleException(Exception ex, String policyName)
   Business.CategorySystem.GetCategories() in G:\book\asp.net\new\code\book12\Business\CategorySystem.cs:30
   book12.module.Category.Page_Load(Object sender, EventArgs e) in G:\book\asp.net\new\code\book12\book12\module\Category.ascx.cs:23
   System.Web.UI.Control.OnLoad(EventArgs e) +67
   System.Web.UI.Control.LoadRecursive() +35
   System.Web.UI.Control.LoadRecursive() +98
   System.Web.UI.Control.LoadRecursive() +98
   System.Web.UI.Page.ProcessRequestMain() +2106
   System.Web.UI.Page.ProcessRequest() +217
   System.Web.UI.Page.ProcessRequest(HttpContext context) +18
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication+IExecutionStep.Execute() +179
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +87