Access denied when deleting Registry (even in regedit)

I'm trying to delete a Windows registry using Delphi but without success (even with Regedit itself I can not).

Code I'm using:

Function DeleteKeyAPI(hRoot: HKEY; sPath: String; IsReg64: BOOL): BOOL;
Var
  iRet: Integer;
Begin
  If IsReg64 Then
    iRet := RegDeleteKeyEx(hRoot, PChar(sPath), KEY_WOW64_64KEY, 0)
  Else
    iRet := RegDeleteKeyEx(hRoot, PChar(sPath), KEY_WOW64_32KEY, 0);

  If iRet = ERROR_SUCCESS Then
    Result := True
  Else
    Result := False;
End;

Error message when I try to delete by Regedit:

But when I delete the software (PC Hunter) it is deleted successfully. How can I delete this registry?