Try going through an anonymizer like anonymouse.org and see if you can at least GET to the site from your home. This will eliminate things like DNS for YOUR ISP, DNS settings at the router, blocking by YOUR ISP, etc..

If you still cannot get to it that way, check to see if you have something like mcafee, norton, avg safesearch, webroot security which is actively filtering your safe sites list. MANY times these tools do NOT give any feedback that they are working in the background - at least not consistently.

If you go to THIS site, and type in the URL you are trying to reach, it will TELL you the IP address of the site, which you can then easily ping with either tools or a command line.

http://www.selfseo.com/find_ip_address_of_a_website.php

Start, RUN, CMD, type in PING at the command prompt and then type in the IP address that the above site lists for you.

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