No internet connection. My laptop does not connect to the internet. It first happened at school

Question

My laptop does not connect to the internet. It first happened at school when it would connect to the school's network but not to the internet. I then tried it through a dialup connection, which dials and claims to be connected at a blazing 31 kps, but will not open web pages or perform other functions such as liveupdate from symantec. It has always worked before and the change was quite sudden.