So a lot of people use Ad Block Plus, anti-virus and anti-spyware software and other things to keep their computer clean from infection and unwanted content. Not many people talk about blocking these things using host files. This is a tutorial, a very simple one, on how to block a lot of nasty content automatically with a host file.
By using a host file, Windows will automatically block any traffic from addresses listed inside of it. Basically a host file is full of web addresses and ip addresses that you want to block all traffic to and from. This blocking doesn't require any software to be used and will block any access to your pc or from, which is good for not only preventing infections from occurring but if you do get infected it could keep the virus/spyware from sending any data from your PC.
The first thing you need to do is download a good host.txt file I have included one to download as an attachment at the bottom of the page. This is from
http://www.mvps.org/ it is a very reputable host file and it is still being updated, the last update (the one attached below) was done on Sep. 22 2010 so it is pretty recent.
I only posted links to the images because I didn't want to go through the trouble of making sure they were the right size and all that, yes I'm kind of lazy sometimes... lol. Alright now let's get down to business.
Step 1. Download the hosts.txt file below and save it to your desktop.
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Step 2. In order to rename the files correctly in the following steps you will need to make file extensions visible. Open Windows Explorer and go to Tools>Folder Options>View and make sure "Hide extensions for known file types" is NOT checked. Once you are done click "Apply" then "OK"
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Step 3. Now in Windows Explorer go to C:\Windows\System32\Drivers\Etc you will see a few files one of them being a very small file called "hosts" notice it has no file extension, this is the way the hosts file has to be when we finish. For editing though we need to rename it to "hosts.txt" so do that now.
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Step 4. Now what you want to do is replace the hosts.txt file with the one on your desktop. Easy peasy, just drag and drop it into Windows Explorer and click yes to replace.
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Step 5. We need to get the file back to it's original file name so just rename it to "hosts" and that's it, no .txt nothing but "hosts" when you do a pop up will come up warning you about changing file extensions just click yes to rename the file.
http://www.fileden.com/files/2009/4/29/2422631/Step%205.JPG-------------------------------------------------------------------------------------------------------
There you have it! All done! Now you are automatically blocking all kinds of malicious software and advertisements no matter what browser you are using all the blocking is done by Windows itself. Now I don't think you need to reboot your PC others will say you do, so it's your call. Rebooting can't hurt right?
Now in the future, when you want to update your host file, just follow these steps again. Only thing is you will have to get your own updated host file by downloading it from here
http://www.mvps.org/winhelp2002/hosts.txt 
