I have a 1700 series router which I need to tweak a couple settings. It was intalled by a computer firm we hired, but have since let go and hired a new firm. They need to access the router, but we don't have the password and old company will not release it. How can we reset the password or recover it? We tried to connect to the router using the RJ45-Serial cable but were unsuccessful. Any advice on this highly critical issue?