In addition to ikegami's advice, you could open the registry in read only mode:
$key= new Win32::TieRegistry "LMachine\\Software\\",
  { Access=>KEY_READ(), Delimiter=>"\\" };

[download]

In reply to Re: In Win32::TieRegistry, what is the best way to tell if a registry variable exists? by runrig
in thread In Win32::TieRegistry, what is the best way to tell if a registry variable exists? by DrWhy

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