I have a similar problem. Our belkin wireless used to have the standard 8 digit code at the bottom. It was an usecured network but occasionally would ask for the key for our customers' use. At this page a password to access these settings was put in on the first line. Everything else was lleft blank with exception of the 8 digit code at the bottom. Now the router won't allow access to the internet without a 5 or 13 letter password. Connecting to the page via cable connection has proved unsuccessful. How do I fix this or can comcast do it for me?
BTW I have reset all our routers still no change...will not return to default. When I try to connect the first attempt says enter password or press button on router. I see no button but the little reset in back. I can get limited connectivity on 3rd try to connect but no internet access and still can't access the router webpage.
describe how you 'reset' your router. If you just did a quick press of the reset button, all that did is reload it, similar to pulling the power cable and plugging it back in. To reset the password if you don't know it, you would have to follow a model specific factory reset, which usually includes holding the reset button for some specified number of seconds.
The other question is, did Comcast supply the router as part of the Home Networking package? If so, you should contact them for support.