TW Cable Modem won’t work with my Netgear Router

I just switched from ATT DSL to Time Warner HiSpeed internet. My netgear router worked fine until today when I switched from DSL to Hi Speed. I can’t seem to get the internet connection detected when I have the ethernet cable plugged into the Netgear router to the Cable Modem. Help! I’ve tried both TW Cable and Netgear support and nothing is working….