If you type HOSTS (just one word) into google.com the first hit is about how to use it and the second is the FAQ. No need to write more here.
Bob
Since December 11, 2007 I have been unable to reach a certain website. Since it is an adult web site I'll not include links. My ISP, Comcast, has not been very helpful in finding the problem. I have attempted connection with both IE and Firefox browsers with the same result.
I have connected other computers to my network and cannot connect, more importantly none of my friends with Comcast can reach it on their computers either.
I did go to the trouble of moving my computer (it is not a laptop I moved the entire tower case), to a home with Time Warner and could reach it with no trouble at all.
Someone here suggested checking my HOSTS file, and said that I should use a different computer, but, as I have said no local computer using any Comcast network can reach the site in question. And no details were given about how to check a HOSTS file. I inadvertently included the link to the website as well as a tracert, but since it is an adult site I have had to repost my problem with edits for more assistance.

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