I had the same thing happen with IE.
Only site affected was CNET (my IE shutdown if I tried navigating this site with it or clicked on any links-- could still reach it thru my favorites menu but no other way).
I am PRETTY sure it was related to Spybot (I had just enabled all Spybot preotections beyond "immunize", ie, host files and IE browser protections).
I found if I reloaded the MS hosts file, the problem went away, but not if I used the MVPS hosts file. I can't swear the two things are at all related, but given that it worked with the Sample Hosts file but not not the MVPS I assume that there is something causal there.
My guess is it has to do with Spybot's settings.
I subscribe to Cnet's Techrepublic, and most of their newsletter's links do not work for me. They once worked, then about 2-3 weeks ago they stopped working for me. They do not work with Maxthon or IE, which I use, and I am using the canned Hosts file that came with the system, so there is nothing in the Hosts file that could prevent them from working. I disabled my virus and firewall software, and still do not work. So something else is astray, and I cannot figure it out.
BTW, the links work with Firefox, so I know they are valid links. I fired off a question to Techrepulic, but they never responded with any possible solutions.
These are the websites that I cannot access, all others I have no problems with:
http://ct.techrepublic.com.com/clicks?c=241372-1721644&brand=techrepublic&ds=5''
and
http://techrepublic.com.com/

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