idmessage1.ContentType:='text/html; charset=windows-1251';
     IdMessage1.Body.text:=UTF8Encode(RichEdit1.text);
     IdMessage1.Subject:=UTF8Encode(edit1.Text); 
     IdMessage1.From.Address:= ComboBox2.Items [ComboBox2.ItemIndex]; 
     IdMessage1.Recipients.EMailAddresses:=edit1.Text; 
     IdMessage1.IsEncoded:=true;


 for i := 0 to form15.ListBox1.Items.Count-1 do
  Begin
  j := ListBox1.Items.Strings[i] ;
   if j <> '' then   attach := TIdAttachmentFile.Create(IdMessage1.MessageParts, j );
  End;

  try
    IdSMTP1.Connect();
    IdSMTP1.Send(form15.IdMessage1);
    showmessage('Сообщение отправлено');
  except
    showmessage('Ошибка при отправке сообщения');
  end;
  IdSMTP1.Disconnect;

  idtTextPart := TIdText.Create(IdMessage1.MessageParts, nil);
  idtTextPart.ContentType  := 'multipart/alternative';
  idtTextPart.ParentPart := -1;

  idtTextPart := TIdText.Create(IdMessage1.MessageParts, nil);
  idtTextPart.ContentType:='text/plain';
  idtTextPart.CharSet := 'windows-1251';
   idtTextPart.Body.Assign(RichEdit1.LINES); // описание в текстовом виде
  idtTextPart.ParentPart := 0;

  idtTextPart:= TIdText.Create(IdMessage1.MessageParts, nil);
  idtTextPart.ContentType := 'text/html';
  idtTextPart.CharSet := 'windows-1251';
  form15.RichEdit1.SelectAll;
      form15.RichEdit1.CopyToClipboard;
  idtTextPart.Body.Add(UTF8Encode(ClipboardToHTML(form15.RichEdit1))); //Текст сообщения);// описание в html виде
  idtTextPart.ParentPart := 0;

   // добавление Attach (по аналогии можно несколько)

  for i := 0 to ListBox1.Items.Count-1 do
  begin
    ATT := TIdAttachmentFile.Create(form15.IdMessage1.MessageParts, AnsiToUtf8(form15.ListBox1.Items.Strings[i]));
    with ATT do
    begin
      ContentType := 'application/octet-stream';
      FileName    := AnsiToUtf8(form15.ListBox1.Items.Strings[i])         ;
    end;
  end;