Delphi Indy 10 SSL and Encoding Issues

When sending mail through Indy components in Delphi 7 encountered periodically on different issues.
Variants of problems:

• sending emails from machines that - there are Russian letters in the names
• email using SSL
• problems with encoding in the subject and body of the message

I didn't find common solution in internet - only scattered pieces.

All solutions brought here. May be it will be useful for someone (tested on russian charsets)

System configuration:

• Delphi 7, 
• Indy components version: 10.5.9.4797 (installed manually by article http://conferences.embarcadero.com/article/32160
  file: Indy10_4798.zip)
• SSL Library: openssl-1.0.0d-i386-win32.zip
  from http://indy.fulgan.com/SSL/
  (files libeay32.dll and ssleay32.dll are copied to project output directory)

main procedure is - SendEmail
Main pieces of code are commented.

uses
...

IdCoderMIME , IdMessage, IdSMTP,
IdSSLOpenSSL , IdIOHandler, IdAttachmentFile, IdExplicitTLSClientServerBase, idCharSets, idText
...

type

  //-- helper stub-class for TidMessage.OnInitializeISO event  handling
  Tindystub = class(tobject)
  public
    procedure OnInitISO(var VHeaderEncoding: Char; var VCharSet: string);
  end;

procedure Tindystub.OnInitISO(var VHeaderEncoding: Char;
  var VCharSet: string);
begin
  VCharSet := IdCharsetNames[ idcs_UTF_8 ];
end;

procedure SendEmail(

    aSmtpServer: string;

    aSmtpPort: integer;

    aSmtpLogin: string;

    aSmtpPassword: string;

    aFromAddress: string;

    aFromName: string;

    aToAddress: string;

    aMessageSubject: string;

    aMessageText: string;

    aAttachmentFileFullName: string;

    aUseSSL: boolean = false

    );

var

  lMessage : TIDMessage;

  lSMTP    : TIdSMTP;

  attach   : TIdAttachmentFile;

  sslHandler: TIdSSLIOHandlerSocketOpenSSL;

  lindystub: Tindystub;

  idtTextPart: TIdText;

begin

  lMessage:= TIDMessage.Create(nil);

  lSmtp:= TIDSmtp.Create(nil);

  sslHandler:= TIdSSLIOHandlerSocketOpenSSL.Create(nil);

  lindystub:= Tindystub.Create();

  try

    lSMTP.AuthType:= satDefault;

    lSMTP.Host     := aSmtpServer;   //Хост

    lSMTP.Port     := aSmtpPort;     //Порт (25 - по умолчанию)

    lSMTP.Username := aSmtpLogin;

    lSMTP.Password := aSmtpPassword;

    //-- solving "non-english computer name" problem

    lSMTP.HeloName := 'tfo';

    //-- using SSL

    if (aUseSSL) then

    begin

      SSLHandler.Destination := aSmtpServer+':'+IntToStr(aSmtpPort);

      SSLHandler.Host := aSmtpServer;

      SSLHandler.Port := aSmtpPort;

      SSLHandler.DefaultPort := 0;

      SSLHandler.SSLOptions.Method := sslvSSLv23;

      SSLHandler.SSLOptions.Mode := sslmUnassigned;

      lSMTP.IOHandler := SSLHandler;

      lSMTP.UseTLS := utUseImplicitTLS;

    end;

    //-- subject encoding

    lMessage.OnInitializeISO := lindystub.OnInitISO;

    lMessage.Subject      := aMessageSubject;

    lMessage.From.Address := aFromAddress;

    lMessage.From.Name    := aFromName;

    lMessage.Recipients.EMailAddresses:= aToAddress;

    //-- message body encoding

    idtTextPart := TIdText.Create(lMessage.MessageParts, nil);

    idtTextPart.ContentType := 'text/plain';

    idtTextPart.CharSet := 'Windows-1251';

    idtTextPart.Body.Text:= aMessageText;

    //-- work with attached files

    if (aAttachmentFileFullName <> '') then

    begin

      attach:=TIdAttachmentFile.Create(lMessage.MessageParts, aAttachmentFileFullName); //Вложение

    end;

    //-- sending email

    lSMTP.Connect;

    try

      lSMTP.Send(lMessage);

    finally

      lSMTP.Disconnect;

    end;

  finally

    sslHandler.Free;

    lMessage.Free;

    lSmtp.Free;

    lindystub.Free;

  end;

end;