Hi ,all MsExchangedAutodiscoverAppPool Starts and stops after sometime , it happened after the Symantec endpoint client upgraded , by mistake the exclusion policy was not set , and the Symantec NAP protection was enabled Error log is below An unhandled exception occurred and the process was terminated. Application ID: /LM/W3SVC/1/ROOT/Autodiscover Process ID: 5020 Exception: System.InvalidOperationException Message: The process 'w3wp' (PID = 5020) has been initialized as Unknown Multiple instance type un-expectedly. Reasons of this exception: 1. For any product executables, which will be shipped out of box, they should never use AD driver functionality without initializing its performance counter instance since we can NOT show a intuitive Perf Counter instance name here. 2. We don't need the validation for test assembly because we don't care for its performance counter naming; however, we definitely want to make sure it is under our control, so that we don't miss any out of box product DLLs/EXEs. What to do to avoid this exception: For any newly added Exchange test executables which utilize AD perf, please add the executable name of the process into exclusion list in Microsoft.Exchange.Data.Directory.Globals.CheckExchangeTestExecutables. StackTrace: at Microsoft.Exchange.Data.Directory.Globals.InitializePerfCounterInstance(String applicationName, Boolean hasMultiInstance) at Microsoft.Exchange.Data.Directory.ADProviderPerf.AddDCInstance(String serverName) at Microsoft.Exchange.Data.Directory.LdapConnectionPool.CreateOneTimeConnection(NetworkCredential networkCredential, ADServerInfo serverInfo) at Microsoft.Exchange.Data.Directory.TopologyProvider.PopulateConfigNamingContexts() at Microsoft.Exchange.Data.Directory.TopologyProvider.GetConfigurationNamingContext() at Microsoft.Exchange.Data.Directory.ADSession.GetConnection(String preferredServer, Boolean isWriteOperation, Boolean isNotifyOperation, ADObjectId& rootId) at Microsoft.Exchange.Data.Directory.ADGenericReader.GetNextResultCollection(Type controlType, DirectoryControl& responseControl) at Microsoft.Exchange.Data.Directory.ADPagedReader`1.GetNextResultCollection() at Microsoft.Exchange.Data.Directory.ADPagedReader`1.GetNextPage() at Microsoft.Exchange.Data.Directory.ADPagedReader`1.<GetEnumerator>d__0.MoveNext() at Microsoft.Exchange.Autodiscover.Providers.Outlook.OutlookAutoDiscoverProvider.SimpleConfigCache`2.Freshen(ADSystemConfigurationSession session) at Microsoft.Exchange.Autodiscover.Providers.Outlook.OutlookAutoDiscoverProvider.UpdateCacheCallback(Object stateInfo) at System.Threading.ExecutionContext.runTryCode(Object userData) at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Threading._TimerCallback.PerformTimerCallback(Object state) Pls help 3005 An unhandled exception has occurred. 12/19/2010 4:36:05 PM 12/19/2010 1:36:05 PM 735acd8656d24444b4fd5f448a02eca2 2 1 0 /LM/W3SVC/1/ROOT/Autodiscover-1-129372393630581716 Full /Autodiscover C:\Program Files\Microsoft\Exchange Server\ClientAccess\Autodiscover\ MREXCA02 6828 w3wp.exe NT AUTHORITY\SYSTEM Win32Exception Access is denied https://MREXCA02.DOMAIN.local:443/Autodiscover/Autodiscover.xml /Autodiscover/Autodiscover.xml 10.0.10.32 False DOMAIN\AutoDiscover 3 DOMAIN\AutoDiscover False at System.Diagnostics.ProcessManager.OpenProcess(Int32 processId, Int32 access, Boolean throwIfExited) at System.Diagnostics.NtProcessManager.GetModuleInfos(Int32 processId, Boolean firstModuleOnly) at System.Diagnostics.Process.get_MainModule() at Microsoft.Exchange.Security.Privileges.RemoveAllExcept(Process managedProcessHandle, String[] privilegesToKeep, String processLabel) at Microsoft.Exchange.Autodiscover.Global.Application_Start(Object sender, EventArgs e) MsExchangedAutodiscoverAppPool Starts and stops SSS

Hi, Does the issue persist after disabling Symantec NAP protection?Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. Thanks Gen Lin-MSFT

yes it still persist, it was symantec NTP not NAP Thanks