This worked great for me. Just use as function and kill as many processes as you like.

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KillProc "abc.exe"

Sub KillProc( myProcess )    

Dim blnRunning, colProcesses, objProcess    

blnRunning = False    

Set colProcesses = GetObject("winmgmts:{impersonationLevel=impersonate}").ExecQuery( "Select * From Win32_Process", , 48 )    

For Each objProcess in colProcesses        

If LCase( myProcess ) = LCase( objProcess.Name ) Then             ' Confirm that the process was actually running             blnRunning = True             ' Get exact case for the actual process name            

 myProcess  = objProcess.Name             ' Kill all instances of the process            

objProcess.Terminate()        

 End If    

 Next    

 If blnRunning Then        

Do Until Not blnRunning            

 Set colProcesses = GetObject("winmgmts:{impersonationLevel=impersonate}").ExecQuery( "Select * From Win32_Process Where Name = '"& myProcess & "'" )            

WScript.Sleep 100 'Wait for 100 MilliSeconds            

If colProcesses.Count = 0 Then 'If no more processes are running, exit loop                

 blnRunning = False            

End If        

Loop      

End If

End Sub