All sites are running smoothly in my computer,but www.hi5.com is not running.Plz help me to fix this problem.?

I have been using Internet Explorer 7 and Mozilla for browsing the net.But none of this opens the site www.hi5.com.

All sites are running smoothly in my computer,but www.hi5.com is not running.Plz help me to fix this problem.?
It may be a problem with your ISP, get it checked