Whenever I try to secure the default wireless network named "Linksys", it just duplicates itself ie I have a secured network with the name I chose and I still have the non-secure Linksys network. How can I delete the non-secure one?
Whenever I log into the router administration page (after connecting to the Internet with an Ethernet cable and being connected to the non-secure network) , the page just lists the secure network. It seems the router acknowledges only one valid network, the secure one, and that the non-secure one is just a ghost. The problem is that my roommates and the neighbourhood can still pick up the signals of both networks, the secure and non-secure one, and my limit of downloading is always exceeded.
1. You should never use the default SSID "linksys". You should also make it a unique SSID. Otherwise your computer may try to connect to your neighbor's router instead of yours.
2. Windows remembers wireless networks. You have to delete the old non-secure network from the list of preferred networks to get rid of it. After you have secured the wireless you don't "have the non-secure Linksys network". It's just that Windows see a network called "linksys" and shows all saved wireless networks with that SSID.
Thus the problem is not the router or that a computer "picks" up a non-secured signal (unless again, you really have another linksys router with default settings in the neighborhood) but the computer has a list of networks it knows and shows that.
Remove all linksys (SSID linksys) networks from the list of preferred networks from all your computers. Make sure to set up a unique SSID instead and secure that. That should do it.
If computers still pick up a unsecure linksys network after you clear the list of preferred networks it may be a different router. Unplug your router from power. Then search again for networks in the neighborhood. If the linksys still appears (probably with a weaker signal than before) it's not your router.