One day internet (cable modem) works fine, next get this message in tray. Have two computers with router, other computer internet OK, changed ports as well as connecting directly to modem, still nothing. Renew IP does not work with similar reason.
Please what next?

I don't know and have never really been able to figure out the problem, but here are some things I've done to make it re-connect for myself when that happens... I've got wireless connection from a wireless router which is fed through the cable modem.. These steps may or may not work on hard line cable.

1.) If your computer is using a router, unplug the router for 1 min and then plug it back in. Check to see if your computer re-connects.

1a.) If it does great, but if not then REPAIR the connection by right clicking on the icon and going to repair. If this doesn't work, then move to #2.

2.) Check to make sure your cable modem is getting its signal from the service provider like normal. If you don't know how to tell, just call them and ask if there are any service outages for cable modem connections in your area. If yes, then just wait a bit and it'll be back up... If not, move to #3.

3.) Go to Control Panel, Network Connections, Look for LAN or HIGH SPEED INTERNET section. Under that section double click your connection. A window should pop up. Then click VIEW WIRELESS NETWORK. Then on the left click CHANGE ADVANCED SETTINGS. Then at top click VIEW WIRELESS NETWORKS. A window will pop up. You should see your wireless routers name in the white box. REMOVE IT (make sure if its password encrypted you know the pw before doing this). Then click OK at the bottom of that window. Close any other windows that were open in this process. Now down at the bottom you will have a window icon with red X. Double click that to bring up a new window. Double click your connection and if pw required then type it in. Click CONNECT.

let me know if any of this helps!

Jeremy