Shoutbox

Your nickname is only noticed by somebody when they're online at the same time as you. Until they come online, they won't see your nickname. With other words, you would need to, whenever one of your blocked contacts come online, change your nickname, unblock them, block them again, change your nickname back. And by the way, what's the point of doing that? This way the blocked person knows you're online..

By the way blocking all people on your contact list is a very extensive thing to do; for one, do it too much, and you'll loose your account. Msn'll block it. Secondly, it would take ages to block your entire contact list if it's larger than a few dozen contacts.