How can i get msn to work?

My msn messenger hasn't been working for about a month now, as it says "signing into Windows Live Messenger has failed because the service is currently unavailable. Please try again later". I've uninstalled msn, and installed it again many times but it still won't work. I've been using ebuddy etc, however ebuddy doesn't allow me to use my webcam like msn. Any help?! thankyou :)