This question was posted on my site's forum too. If you are a windows user, then the least you can do is activate the standard firewall by going to my network places, right clicking ur internet connection and clicking properties. In the advanced tab check the box firewall, and click ok. if you are not using windows or prefer to go more advanced, then you can always purchase mcafee personal firewall plus.
I don't suggest you activate the firewall if you have a home network, a networked printer or a networked internet connection because it can disturb access to those products.
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