VB Script to see apppool status.

i am running below script to get the app pool status. i am getting below error. can anyone help me on this
 
Line:6
Char:1
Error : Invalid namespace.
 
code
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StrServer = "server1"
Set locatorObj = CreateObject("WbemScripting.SWbemLocator") locatorObj.Security_.AuthenticationLevel = WbemAuthenticationLevelPktPrivacy   Set ProviderObj = locatorObj.ConnectServer(strServer, "domain\username")   strQuery = "Select * from IIsApplicationPoolSetting"   For Each Item In ProviderObj.ExecQuery(strQuery)   AppName = Replace(Item.Name, "W3SVC/AppPools/", "")         Select Case Item.AppPoolState     Case 1       State = "Starting"
Case 2       State = "Running"
Case 3       State = "Stopping"
Case 4       State = "Stopped"
Case else       State = "unknown"
End Select 

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