Check your hosts file. Remove anything that isn't necessary or isn't the localhost loopback.
Change your DNS settings. Use OpenDNS or Google Public DNS. Clear Windows' DNS cache (should automatically clear when you swap dns servers)
If else fails, call your provider's support line.
Also if you're running some bullstuff "internet speedup" or other form of bloatware, uninstall it.
Blueblur, you have no idea what you're talking about. Stop trying.