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Need to get result of WMI query for error handling

I have vbscript that uses WMI to enumerate all 32 and 64 bit processes. Then it takes the results and does another WMI query to get the loaded DLL's. It works most of the time, but often gets an automation error saying "unknown error". I realized that it is getting the list of processes and while it is queying for loaded drivers, a process stops and so when the script tries to get the loaded DLL's of a process that no longer exists, I get an error when I try to use the results of the query. Obviously I need to check to see if I have a valid object before I use it, but it seems that nothing I do works to see if it is valid. The code is posted below. Here are the functions I have tried.
IsNull
IsObject
IsEmpty
Is Nothing
obj.Count

Set objWMIService = GetObject("winmgmts:" & "{impersonationLevel=impersonate,(Debug)}!\\" & "." & "\root\cimv2")

processPid = 6000 'ANY INVALID PID

strAssocQuery = "ASSOCIATORS OF {Win32_Process.Handle='" & processPid & "'} WHERE ResultClass=CIM_DataFile"
Set colModule = objWMIService.ExecQuery(strAssocQuery, , 48)

'NEED WAY TO MAKE SURE THAT colModule is valid

For Each module In colModule 'GIVES ERROR HERE WHEN INVALID PID
     msgbox module.Name      
Next

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RobSampson

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ASKER

That did it, thanks

connectex

Add this code:

processValid = false
Set colProcessList = objWMIService.ExecQuery ("SELECT * FROM Win32_Process WHERE ProcessID = ' & processPID & "'")
For Each objProcess in colProcessList
processFound = true
Next

Now if process is found it's still active or valid and you should be able to query it.