When I get into where you type in your username and password it will not take any of the suggested info - I get a message after 3 tries - 401 unauthorized. I never did set a password when I installed the router - I thought I would do it later. Now I can't seem to get into it to set one.
You can see some of the router settings but not change them without knowing the password to access it. Is that the password you're missing? Try admin as the login and password or admin as the password. If they don't work, post back the make and model of the router and someone will know the details.