@cactusjuice92: I wish that were true, but evidence is pointing to whitelisted IPs in the HOSTS processing code. Watch your back. :MJ
If the IPs are known, you could block them at the router level if you have open-source firmware like OpenWRT or DD-WRT.
Certainly the best bet is to try and block it outside of Windows, MS may let you do many things, but in the end, do we know if it really is doing anything, or just something to make us "think" we have a choice.