Block Msn Messenger

STEP 1: BLOCK PORT 1863.

STEP 2: DO LIKE THIS:

MSN Connection Overview

All connections to MSN servers take place over TCP/IP. The client always makes the outgoing connections to the servers. The official port for MSN Messenger is 1863, although there are many places in the protocol where alternate ports could be specified, so this may be subject to change.

The connection to the server must be considered asynchronous - you can send many commands to the server without waiting for a reply, and the server won't necessarily reply to your commands in the order you sent them. The server may also send messages that are not in reply to any particular message from the client. However, sometimes (for example, when logging into a notification server) the protocol requires you to send one command then receive one command, and so on.

There are also several OOB (out-of-band) protocols that take place directly between clients and do not involve the server. These protocols are described in their respective sections, and are not necessary for basic functionality of a client.

How does HTTP work with MSN?

Microsoft use gateway.messenger.hotmail.com, port 80, as their dispatch server for HTTP connections. Unlike messenger.hotmail.com this server has never been seen to transfer clients to another notification server. However, there is a transfer-like function in MSN's HTTP method.

Though HTTP is most often used for transferring HTML documents (hence the name), it's entirely capable of transferring any kind of data. In HTTP, there is no way for the server to send a message to the client without the client requesting it first. MSN Messenger clients send commands in the body of HTTP an request, and the server queues commands to send in the body of a response. When the client has no commands to send for a few seconds, it should "poll" the server for new messages. The official client polls the server once every two seconds.

Once a client has sent an HTTP request, it must wait for the response to come back before sending another request. For example, if you poll the server then send a command without waiting for the response to the poll, you will receive an HTTP 400 error (bad request).

Normally, a single connection to the server is kept alive throughout an MSN Messenger session, but the protocol seems to support a connection being broken and re-established without the session being affected. This has not yet been tested in practice, though.

In your initial profile, the "ClientPort" is set to 0 in an HTTP connection, and sending PNG will cause the server to send an HTTP error and disconnect you. Otherwise, the protocol works as normal.