There are certain situations where you can't run two instances of same application OR before starting a test with QTP, you want out find out whether a particular process is already running. Ex: In case of Siebel Automation . To find the process, the workflow is, Go to "Windows Task Manager"[Ctrl-Shift-Esc] > Process tab > strain your eyes to sift the required  process from the 100's of already running processes.
We can do this job with a simple VBScript. This will reduce the duration of workflow to < 2 sec and you get the result instantly at the click of a button.
Code:

Dim  AllProcess
Dim  Process
Dim  strFoundProcess
strFoundProcess = False
    Set AllProcess = getobject("winmgmts:") 'create object
    For Each Process In AllProcess.InstancesOf("Win32_process") 'Get all the processes running in your PC
        If (Instr (Ucase(Process.Name),"TASKMGR.EXE") = 1) Then 'Made all uppercase to remove ambiguity. Replace TASKMGR.EXE with your application name in CAPS.
             msgbox "Application is already running!" 'You can replace this with Reporter.ReportEvent
            strFoundProcess = True
            Exit for
       End If
    Next
     If strFoundProcess = False Then
     msgbox "Go ahead!Application is not running" 'You can replace this with Reporter.ReportEvent
    End If
Set AllProcess = nothing

To check whether this is working:
1) Copy the above code to a notepad and save file as test.vbs on your desktop.
2) Open the Windows Task Manager[Ctrl-Shift-Esc].
3) Double click on file created above(test.vbs)
4) You should get a message "Application is already running!"
5) Done...Enjoy!

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