Microsoft Message Queuing

First of all you have to install MSMQ. You will do it through Control panel->Add remove programs->Add/Remove Windows components.

Second you will need to access MSMQ for managing, you can do it through Computer Management->Services and Applications->Message Queuing

Now, create one queue, for example "test", under Private Queues.

Then, send a message through Delphi :)

Here is the code:

For sending messages:

procedure TForm3.Button1Click(Sender: TObject);
var
  queuename, subject: string;
  data: olevariant;
  queueinfo, QueueInfosObj: IMSMQQueueInfo;
  queue, QueryObj: IMSMQQueue;
  msg: IMSMQMessage;
  tr: OLEVariant;
begin
{ STANKO is name of my computer, test is name of queue}
  queuename := 'Direct=OS:STANKOprivate$	est';
  subject := Edit1.text;
  data := Memo1.text;

  try
    queueinfo := CreateCOMObject (CLASS_MSMQQueueInfo) as IMSMQQueueInfo;
    queueinfo.FormatName := queuename;
    queue := queueinfo.Open (MQ_SEND_ACCESS, MQ_DENY_NONE);
    if queue.IsOpen  1 then
      statusbar1.Panels[0].Text := 'I can not get access to queue!'
   else
   begin
     try
       msg := CreateCOMObject (CLASS_MSMQMessage) as IMSMQMessage;
       msg.label_ := subject;
       msg.body := data;
       tr := MQ_NO_TRANSACTION;
       msg.Send (queue, tr);
       statusbar1.Panels[0].Text := 'Sent!'
     finally
       queue.close;
     end;
  end;
  except
    on e: exception do showmessage (e.message);
  end;
end;

Now, for receiving messages:

procedure TForm3.Button2Click(Sender: TObject);
var
  queuename: string;
  data: olevariant;
  queueinfo: IMSMQQueueInfo;
  queue: IMSMQQueue;
  msg: IMSMQMessage;
  tr, wdq, wb, rt: OLEVariant;
begin
  queuename:= 'Direct=OS:STANKOprivate$	est';
  try
    queueinfo := CreateCOMObject (CLASS_MSMQQueueInfo) as IMSMQQueueInfo;
    queueinfo.FormatName := queuename;
    queue := queueinfo.Open (MQ_RECEIVE_ACCESS, MQ_DENY_NONE);
    if queue.IsOpen  1 then
      statusbar1.Panels[0].Text := 'I can not get access to queue!'
    else
    begin
      try
        tr := MQ_SINGLE_MESSAGE;
        wdq := False;
        wb := True;
        rt := 1000;
        msg := queue.Receive (tr, wdq, wb, rt);
        if msg nil then
        begin
          data := msg.body;
          statusbar1.Panels[0].Text := 'Received!';
          memo2.text:=data;
          edit2.text:=msg.label_;
        end
        else
          statusbar1.Panels[0].Text := 'No messages'
      finally
        queue.close;
      end;
  end;
  except
      on e: exception do showmessage (e.message);
  end;
end;

Code taken from here. It is on Slovenian, but I coudn't find it on English.

Here you can download source code created in D2007, and here is the exe file.