Can't play while friend's computer is on

Recently I moved in to a friend's house and convinced him to start playing Lol. However, when he turns on his computer (which is a laptop with Windows 8) we get all sorts of weird bugs with connection.

First of all, he has to do all the weird steps needed to make Lol work with Windows 8 (like making sure that Internet Explorer is at the default settings, resetting the client after each game, etc).

However, the worse bit comes in that when both of us want to play at the same time, sometimes one or both of the games are completely unplayable - I do not see the invites from my online friends, I get randomly disconnected from pvp.net, when I'm in the game queue I do not see if the match was found, it then appears with a delay and when I accept it it says "no game was found".

It only happens sometimes and when he turns out the internet on his computer, usually everything works fine. However in the long run this issue makes the game more or less unplayable.

Therefore I ask - has anyone had such a problem before? Is it a matter of internet configuration (frankly it looks as if his laptop had some kind of a "privilege" so that all internet first goes to him and only then to the other computers in the network) and if so, how could I change it?

If you have any advice on what could that friend do with his laptop to make lol run more smoothly, that would be nice as well.

I would be very grateful for any help.

It has to be one of two things. Either there is an IP conflict on your LAN. You can run the command ipconfig /all from command prompt and find your IP address. If it matches your friend's address then you will have all kinds of connection problems.

Most likely though, it is because, as far as LoL servers are concerned, you and your friend have the same IP address. This is because when your data traffic goes out to the internet it is stamped with an external IP address from your ISP's modem. This is the same for all outbound traffic from your ISP demarc. I am not 100% sure, but I believe LoL does do IP blocking for the same IP traffic.d