Event Code: 3005 An unhandled exception has occurred.

Event code: 3005 Event message: An unhandled exception has occurred. Event time: 2/19/2009 1:41:40 PM Event time (UTC): 2/19/2009 6:41:40 PM Event ID: 83d95f94ac674e39889a37e4d558a865 Event sequence: 2477 Event occurrence: 300 Event detail code: 0  Application information:     Application domain: /LM/W3SVC/XXXXXXXXXXX/Root-1-XXXXXXXXXXX     Trust level: Full     Application Virtual Path: /     Application Path: C:\XXXXX\XXXXX     Machine name: XXXXXXXXXXX  Process information:     Process ID: 1860     Process name: w3wp.exe     Account name: NT AUTHORITY\NETWORK SERVICE  Exception information:     Exception type: NullReferenceException     Exception message: Object reference not set to an instance of an object.  Request information:     Request URL:      Request path:      User host address:      User:      Is authenticated: False     Authentication Type:      Thread account name: domain\username  Thread information:     Thread ID: 8     Thread account name: domain\username     Is impersonating: False     Stack trace:    at ASP.global_asax.Session_End(Object sender, EventArgs e)

解决方法：
If I remember correctly, I resolved this by turning off the health monitoring in dot net. You can turn it off via the web config. Of course, when you make the change, stop and start your web application. This should get them to go away...

<healthMonitoring enabled="false" />

Here is some light reading for you that explains how to use it. I haven't really found any use for it yet :)

http://aspnet.4guysfromrolla.com/articles/031407-1.aspx

<configuration>    <system.web>      <healthMonitoring enabled="true">       <eventMappings>          <clear />          <add name="All Errors" type="System.Web.Management.WebBaseErrorEvent"                   startEventCode="0" endEventCode="2147483647" />       </eventMappings>       <providers>          <clear />          <add name="EventLogProvider" type="System.Web.Management.EventLogWebEventProvider" />       </providers>       <rules>          <clear />          <add name="All Errors Default" eventName="All Errors" provider="EventLogProvider"                   profile="Default" minInstances="1" maxLimit="Infinite" minInterval="00:00:00" />       </rules>      </healthMonitoring>    </system.web></configuration>