Registry ReadString method is not working in Windows 7 in Delphi 7

Question

The following code sample used to return me windows id before, but now it doesn\'t work, and returns empty string, dunno why.

  function GetWindowsID: string         


        

Answer 1

That is because the virtualized key '\Software\Wow6432Node\Microsoft\Windows NT\CurrentVersion\' doesn't contain the 'ProductID' item.

Modify your code to create the TRegistry instance with

Registry := TRegistry.Create(KEY_WRITE OR KEY_WOW64_64KEY);

where KEY_WOW64_64KEY = $0100. That will give you the expected result.

Alternatively, use DSiWin32 and call

DSiReadRegistry('\Software\Microsoft\Windows NT\CurrentVersion', 
  'ProductID', '', HKEY_LOCAL_MACHINE, KEY_QUERY_VALUE OR KEY_WOW64_64KEY);