Courtesy of Robin Walkers cable modem page
Manual Auto-Registration procedure
In order to complete the registration of your cable modem or set top box, and to register for ntlworld username and ISP services, make sure that your PC is using your cable modem connection (not dial-up), then launch your web browser, which
must have
JavaScript enabled. If your web-browser hangs or gives an error page when launched, this might be because it is trying to connect to a home page which is disallowed until you have completed this registration: just click
Stop. Send your web browser to
https://autoreg.autoregister.net/start.html (note the
https rather than http) and follow the on-screen instructions. When asked for a Serial Number:
- for stand-alone cable modem users, the serial number is ntl-ct8-cb485.
- for digital TV set top box users, the serial number is ntl-ct8-cb487.