The usual helps, I guess. I mean, hold the reset button for a while (about 30 seconds) and fix your pc's network ip to the same subnet with the router's original ip address. That you'll find from the manual. Then type that address into the browser. Most of the original name/password -combinations in Buffalo's devices would be root/- (blank). That way you can change the router's information back to those that fit your network. Remember to have your pc to go alongside the same subnet with the router all the time.
