Why can't I change or modify the hosts file in Windows even though I'm logged in through the administrator account itself?

I just did exactly that, a couple of hours ago. Using Windows Explorer, navigate to 'hosts', right click 'properties', tab for 'Security' choose 'Users', click edit, and add write privileges for users. That's the bold black check mark above. Make your changes. If you wish, you can change the permissions back after your edit. Note that the page referenced below suggests, for Win 8.1, that if you are going to route some sites to a dead end, you use 0.0.0.0 in place of 127.0.0.1; that is: network unavailable, not localhost. And that you exclude hosts from your Windows defender, or it will detect your changes as malicious. Windows Defender is a control panel item. Look for settings tab; menu item for excluded files; browse to hosts; add; and save. Finally, if you are editing hosts using Notepad or Wordpad, don't let them add an extension like .txt or .rtf etc when saving the new hosts file. The name of the hosts file is just hosts . Use file types 'all files *.*' when you are saving. winhelp2002.mvps.org/hosts.htm (General) winhelp2002.mvps.org/hostswin8.htm (Win8)