Inno-Setup doesn't allow access to all registr

Question

I use this code to know if a key exists or not :

  if RegKeyExists(HKEY_LOCAL_MACHINE, 'Software\Autodesk') then
  begin
    MsgBox('Key exists!!', mbInformation, MB_OK);
  end;

for this exemple, it works, i have the message box, but with this it doesn't:

  if RegKeyExists(HKEY_LOCAL_MACHINE, 'Software\Autodesk\Maya') then
  begin
    MsgBox('Key exists!!', mbInformation, MB_OK);
  end;

But the 'Maya' key exists on my computer. Can anybody help me ?

EDIT :

In fact, it seems that inno-setup don't access to the right keys... For exemple, with this code I list all the subkeys of HKEY_LOCAL_MACHINE\SOFTWARE, but (!) the result is all subkey of HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node ...

  if RegGetSubkeyNames(HKEY_LOCAL_MACHINE, 'SOFTWARE', Names) then
  begin
    S := '';
    for I := 0 to GetArrayLength(Names)-1 do
      S := S + Names[I] + #13#10;
    MsgBox('List of subkeys:'#13#10#13#10 + S, mbInformation, MB_OK);
  end;

why this Wow6432Node key ?

Answer 1

Are you sure that Software\Autodesk\Maya is a registry key? Maybe it's just a value and you have to use RegValueExists.

Answer 2

It's not InnoSetup's fault at all; the Registry is virtualized in Vista & higher, and on 64-bit there are branches for native 64-bit and WOW'ed 32-bit.

In this case, since InnoSetup is a 32-bit program, the OS directs all of its HKLM\Software Registry requests to the WOW6432Node.

To handle the registry virtualization in your installer, you can specifically use x86 and x64 key roots. For example, use "HKLM32" or "HKLM64" in your [Registry] section when you need to differentiate. In [Code] section, wrap registry helper function calls using HKLM64 in an 'if IsWin64' block.

This example works ok from our installer, whether or not the installer is declared as an x64 installer.

function Mobu120x64IsAvailable(): Boolean;
var
  resultString: String;
begin
  resultString := 'No';
  if IsWin64 then
  begin
    Result := RegValueExists(HKLM64, 'SOFTWARE\Autodesk\MotionBuilder\2012', 'InstallPath');
    if Result then begin
      resultString := 'Yes';
    end;
    Log('Win64: Found Mobu 12.0 for x64?:' + resultString);
  end;
end;

Answer 3

Let me guess... you're on Windows 7 64-bit?

It's not InnoSetup's fault at all, it's that the Registry is virtualized in Vista & higher, and on 64-bit there are branches for native 64-bit and WOW'ed 32-bit.

In this case, since InnoSetup is a 32-bit program, the OS directs all of its HKLM\Software Registry requests to the WOW6432Node.

If your program is 64-bit, then you want to use a 64-bit setup program too.