Chamar programa de envio de Email padrão Rad Studio XE8

function EnviarEMail(const De, Para, Assunto, Texto, Arquivo: string;
                     Confirma: Boolean): Integer;
var
  Msg: TMapiMessage;
  lpSender, lpRecepient: TMapiRecipDesc;
  FileAttach: TMapiFileDesc;
  SM: TFNMapiSendMail;
  MAPIModule: HModule;
  Flags: Cardinal;
begin
  // Cria Propriedades da Mensagem
  FillChar(Msg, SizeOf(Msg), 0);

  with Msg do
  begin
    if (Assunto <> '') then
      lpszSubject := PAnsiChar(Assunto);

    if (Texto <> '') then
      lpszNoteText := PAnsiChar(Texto);

    // Remetente
    if (De <> '') then
    begin
      lpSender.ulRecipClass := MAPI_ORIG;
      lpSender.lpszName     := PAnsiChar(De);
      lpSender.lpszAddress  := PAnsiChar(De);
      lpSender.ulReserved   := 0;
      lpSender.ulEIDSize    := 0;
      lpSender.lpEntryID    := nil;
      lpOriginator          := @lpSender;
    end;

    // Destinatário
    if (Para <> '') then
    begin
      lpRecepient.ulRecipClass := MAPI_TO;
      lpRecepient.lpszName     := PAnsiChar(Para);
      lpRecepient.lpszAddress  := PAnsiChar(Para);
      lpRecepient.ulReserved   := 0;
      lpRecepient.ulEIDSize    := 0;
      lpRecepient.lpEntryID    := nil;
      nRecipCount              := 1;
      lpRecips                 := @lpRecepient;
    end else
      lpRecips                 := nil;

    // arquivo anexo
    if (Arquivo = '') then
    begin
      nFileCount := 0;
      lpFiles := nil;
    end else
    begin
      FillChar(FileAttach, SizeOf(FileAttach), 0);
      FileAttach.nPosition    := Cardinal($FFFFFFFF);
      FileAttach.lpszPathName := PAnsiChar(Arquivo);
      nFileCount              := 1;
      lpFiles                 := @FileAttach;
    end;
  end;

  // Carrega DLL e o Método para Envio do Email
  MAPIModule := LoadLibrary(PChar(MAPIDLL));

  if (MAPIModule = 0) then
    Result := -1
  else
  begin
    try
      if (Confirma) then
        Flags := MAPI_DIALOG or MAPI_LOGON_UI
      else
        Flags := 0;

      @SM := GetProcAddress(MAPIModule, 'MAPISendMail');

      if (@SM <> nil) then     
        Result := SM(0, Application.Handle, Msg, Flags, 0)
      else
        Result := 1;

    finally
      FreeLibrary(MAPIModule);
    end;
  end;
end;