Hi,

In my household, my computer is the one that is connected to the router. Just recently, my internet on all off my family members computers is fine, but mine is not working. There is a message that keeps saying there is a problem with my Local Area Connection, but I have no idea what to do. I can't connect to the internet at all, my Firefox keeps getting errors that says server is not found. I'm not sure how to resolve this and whether this is also a conflict with a firewall.

You shouldn't have any issues with a firewall if it has been installed the whole time you've used LAN connection. I say disconnect the router and reconnect to it and recreate your internet log in. Best of luck!

Try the easiest fixes first, if you have a spare Cat5 (Ethernet) cable then swap it to see if the cable is the issue.