How to block a web site in Windows Vista

Sometimes you may need to block web site. You can easily achieve this by using Windows Hosts file. Hosts file is located in C:\WINDOWS\SYSTEM32\DRIVERS\ETC. Open that in Notepad. As an exaple if you want to block the site www.example.com include this lines at the bottom of the file.

127.0.0.1 example.com
127.0.0.1 www.example.com

You can find more information regarding this in gohacking