You should have created a personalized username and password when you first set up the router.
If you haven't, then leave the "User name" box blank, and in the "Password" box, enter "admin." If that doesn't work, type "admin" into the "User name" box as well. Check that your router is running the latest firmware.
I contacted Cisco and was told that no firmware updates are available for my router since it is out of warranty.
I contacted Amazon and was told that the problem was in my router.
In the upper-right-hand corner of the screen, you should see the words "Firmware Version" and then several numbers. If that's the number you see, then skip to step 12.