Can someone please help me out with my problem...

I tried to sign into MSN messenger (version 6.0) today
and for some reason it won't let me in! It keeps coming
up with this annoying message saying, "We were unable to
sign you in to .NET Messenger Service, possibly because
of a problem with the service or with your internet
connection. Please make sure that you are connected to
the Internet." I've tried everything...I tried
reconnecting to the internet, shutting down my computer
and then rebooting it and connecting to the internet
again but nothing will work! I would greatly appreciate
it if someone could help me out.