It could be improperly set Firewall (or VPN) from some other company installed on your computer.
Perhaps, your network isn't configured right.
If you can use a browser from that computer to visit websites, then something is wrong with your OS and some software installed on it.
If you can't, then maybe your hardware isn't working properly.
I would recommend calling a service guy from some computer help service, or maybe from the place you bought your computer at.
You really need some tech support about that issue.