Reset the router. There will be a button for that on the back of it somewhere.
the router is Billion by the wayshady said:I accidentally set the subnet mask of router to 255.255.255.255
it was supposed to be 255.255.255.0
You can't access the router. That's all there is to it. You have to reset it. It's not a big deal. So you have to reenter a couple of settings. That can't be the end of the world, can it?