>>>>It's not MSN it's built-in Windows Messenger Service. In particular, NET SEND uses it to send messages between Pc's.
>>>
>>>That's what I meant. The Windows MSN Messenger. Whenever it's running, those messages are coming in. If it's not running, they're not.
>>
>>Than we're talking about two different types of spam. The one with Windows Messenger Service doesn't require presence of MSN Messenger at all.
>
>Well, I started to get them since two weeks. When MSN is not running, I don't get them. So, I assumed it was related. Even if the taskbar is not showing MSN, if the little head MSN appears in the tray, then, it'll do the same. Are we really sure that this takes effect even if that is shutted off?

I don't have MSN Messenger installed on my home PC but I received a few popup spams this way until we turned off port 135 on our firewall.