Possibly you've got some intruders that inhibit visiting these sites to make sure they won't be detected. Things to try (ask for more information if necessary):
- rename hosts
- online scan with panda or housecall
- study the msconfig startup list
It might be difficult to find.
I have Windows XP and use Norton Firewall, Norton AntiVirus,Webroot Spy Sweeper,Ad-Aware SE Personal and Spybot 1.3. In the Spy Sweeper window at the bottom right, if I click over the keyhole that reads " Click here to visit Webroot site " nothing happens. With Norton Firewall when I click " Check Security " nothing happens, also with Ad-Aware, when I click for upgrade information , again nothing happens. I would be grateful for any help.