Sometimes the lights on your modem don’t look ok because your modem isn’t set up quite right. Using a DSL filter on the modem line and connecting the phone cord to the wrong port are a couple of common mistakes.
Check the DSL line connecting your modem to the wall jack. It shouldn’t have a DSL filter on it. If it does, remove it.
DSL filters split the signal coming into your home between your phone and the internet. They’re important, and you’ve probably been told to put DSL filters on all devices in your home that connect to your phone line. That’s true. EXCEPT for your modem.
If you install a filter on the modem, you’re stopping the DSL signal from traveling to the modem (which you don’t want to do). Conversely, if you have a phone and do not install a filter, the DSL signal will interfere with your phone, causing noise and making your phone unusable.
Be sure to plug the phone cord — which is coming from the wall jack — into the port on the back of your modem labeled, DSL (or LINE). DO NOT plug it into the port labeled, PHONE. That port is filtered and is meant for connecting your telephone to your modem.