I have a Linksys router on my wired network and I don't know if the process is the same, but to get into the router setup utility I have to type this into the browser click here
I then get a security screen and Linksys say to enter nothing in the user name and then admin for the password. Once you are in set up your security then change the password to something more secure before you leave the setup utility. Obviously you will need to remember this should you ever want to enter the utility again.
I'm sorry if this is what you've been trying already, but it's not clear from your post. Anyway I hope it helpd