function ReadKey(Path: String; Value: String): String;
var
  reg: TRegistry;
begin
  reg:=TRegistry.Create;
  try
    reg.RootKey:=HKEY_LOCAL_MACHINE;
    reg.OpenKey(Path, False);
    Result:=reg.ReadString(Value);
    if Result = '' then
      Result:='Unknown';
  except
    Result:='Unknown';
  end;
end;

function GetCDriveSN: String;
var
  pdw: pDword;
  mc, fl: Dword;
  dwSerial: Dword;
begin
  New(pdw);
  GetVolumeInformation('C:\', nil, 0, pdw, mc, fl, nil, 0);
  dwSerial:=pdw^;
  Dispose(pdw);
  Result:=IntToStr(tmp);
end;

function GetHardwareID: string;
var
  tmp, tmp2: String;
  FileData: THWProfileInfo;
begin
  tmp:=md5(ReadKey('Hardware\Description\System\CentralProcessor\0', 'VendorIdentifier'));
  tmp:=tmp + md5(ReadKey('Hardware\Description\System\CentralProcessor\0', 'ProcessorNameString'));
  tmp:=tmp + md5(ReadKey('Hardware\Description\System', 'SystemBiosDate'));
  tmp:=md5(tmp + GetCDriveSN);

  tmp2:=md5(ReadKey('Hardware\Description\System', 'VideoBiosDate'));
  tmp2:=tmp2 + md5(ReadKey('Hardware\Description\System\CentralProcessor\0', 'Identifier'));
  tmp2:=tmp2 + md5(ReadKey('Software\Microsoft\Windows\CurrentVersion', 'ProductID'));
  GetCurrentHwProfile(FileData);
  tmp2:=md5(tmp2 + FileData.szHwProfileGuid);

  Result:=md5(tmp + tmp2);
end;