how can i fix my msn?

OK.... well my computer just got repaired because of a virus and now we have new internet and stuff... but before it got fixed msn was working.. and now its not... when i type in my password and click sign in.. it would just freeze.. even if i type in the wrong password, it just freezes... i tried trouble shooting but that wouldnt work because the first three or four would get ticked.. then when it came to proxy server.. just froze... yea it is really annoying and if you could help that would be aswum :)