We have written about this several times. However, if you still need more convincing, listen to this: Two Florida women had their unsecured wireless network hacked by someone at a local college. The hacker then used their network to subscribe to porn sites.
As mentioned, we have, several times, written about the need to secure your wireless network. You must take every step to prevent unsavory characters from accessing your network. Your network contains personal information, financial information, passwords, pictures and more. Predators want to steal this information; freeloaders just want to use your network to do some secretive things.
Let us know if you need help with this step and we can assist. Simply enter a comment in the box below and we will get back to you.