WAS has encountered an error during the SID mapping for the application pool

Microsoft.Windows.InternetInformationServices.10.0.WAS.has.encountered.an.error.during.the.SID.mapping.for.the.application.pool.Monitor (UnitMonitor)

Knowledge Base article:

Summary

Web sites and Web applications depend on the availability of Internet Information Services (IIS) application pools. IIS application pools in turn depend on the Windows Process Activation Service (WAS). If WAS is not running or errors occur during the startup or shutdown of an application pool, Web sites and Web applications may not be available.

Resolutions

Change the application pool name

To change the application pool name:

Element properties:

TargetMicrosoft.Windows.InternetInformationServices.10.0.ApplicationPool
Parent MonitorSystem.Health.ConfigurationState
CategoryConfigurationHealth
EnabledTrue
Alert GenerateTrue
Alert SeverityError
Alert PriorityNormal
Alert Auto ResolveTrue
Monitor TypeMicrosoft.Windows.InternetInformationServices.10.0.ApplicationPool.EventLogManualReset2StateMonitorType
RemotableTrue
AccessibilityPublic
Alert Message
WAS has encountered an error during the SID mapping for the application pool
{0}
RunAsDefault