What is the hosts file?
The hosts file is a simple text file that is located (for NT/2000/XP) in the %systemroot%system32driversetc directory where %systemroot% is a wildcard that points to the location of your Windows directory (e.g. C:Windows). For Windows 95/98/ME it's in the main %systemroot% directory. It can be edited using Notepad. Be sure that it is saved WITHOUT a file extension of any kind, including type txt. If you make changes and then save the changes, browse to the file through Windows Explorer or My Computer to make sure that the file reads as hosts with no extension. Note: Be sure to set Windows to show file extensions. Think of the hosts file as an address book for web sites. Windows will look in the hosts file BEFORE attempting to locate a web site by using the Internet domain name servers (DNS).
How can we use the hosts file to trick bad sites? The idea here is to give a bad website the wrong address so that any attempt to direct our browser to that address will fail. We do this by telling Windows that the website exists on our computer. Since it does not, the website will fail to load. If we want to block the browser from going to a particular web site, e.g. badsite.com, we can simply add an entry as follows: 127.0.0.1 badsite.com The address 127.0.0.1 is the loopback address of OUR computer, therefore the page will not be found and the lookup will fail.
Automate the procedure.... Spybot S&D, Spy Sweeper and many other anti-spyware programs contain their own list of malware sites that can be added to your hosts file from within the program. For example, Spybot - from the menu, Mode/Advanced/Tools/Hosts file - click on the Add Spybot-S&D hosts lists.
More hosts file info.... Do a search of the Internet for "ad blocking hosts file" and you will locate many lists containing bad sites that can simply be copied and pasted into your hosts file. Click on Easy hosts file management.... Download the Hostess utility from Ray Marron's Hostess page. Hostess is a free utility for maintaining your Hosts file. Cons..... NOTE: If you use this method be prepared to see "Action cancelled" or an x where otherwise you might see an ad or image. This is to be expected since the website that the ad or image points to has been blocked via the hosts file.
Brian Alaway Consulting
Tampa Computer Repair Service and Support