Determine if Adobe Reader is installed

Is there any way to determine if Adobe Reader is installed on the client machine?

I'd like to do this w/o any third party controls.

Thanks in advance!!!

Code:

---

<SCRIPT LANGUAGE="VBScript">
  on error resume next
  useAcrobat = not IsNull(CreateObject("AcroExch.Document"))
  '                or CreateObject("PDF.PdfCtrl.1")

</SCRIPT>

<SCRIPT>
<!--
  if (useAcrobat)
      document.write("Acrobat installed");
  else
      document.write("Acrobat not installed");
//-->
</SCRIPT>

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