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No Internet access with PC connected to a Cisco Cable Modem

paul213 used Ask the Experts™
I recently had a Cisco Cable Modem 2100 (DPC2100R2) installed by Time Warner Cable for Internet access. When I connected my Windows laptop directly to the cable modem with an ethernet cable, my laptop reports "Network, No Internet Access". The cable modem has the following indication lights:

PC - blinking on and off repeatedly
Cable - no light is on
Send - no light is on
Receive - no light is on
Power - the light is on

I still do have a DSL line with a wireless router as a backup Internet source but I made sure these were all not in the mix. I want to make sure my new cable modem is working as expected without moving on to hooking up to a wireless router and then eventually canceling my DSL line.

When Time Warner came over to install the cable modem, the technician made sure the modem was was working and it actually did work on another Windows laptop (which I don't have anymore). The technician did some back and forth talk with Time Warner to reset a thing or two and that's all I know.

What are the troubleshooting steps I should perform now so I can resolve my issue? Thanks.
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JohnBusiness Consultant (Owner)
Most Valuable Expert 2012
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It would appear that Time Warner has tied the MAC address of the first laptop to its system. You need to call Time Warner while you have your computer hooked up to it and ask them to clear the connection settings. They should be able to do this and connect you.

Sometimes powering off the modem, waiting and powering it back on will clear these parameters. That works for me and my ISP. Try this and then call Time Warner if need be.

… Thinkpads_User

The most likely reason you cannot connect is the second thing thinkpads_user said.  Remove power from the modem for 20 seconds, then plug it back in with the laptop connected.  For some reason, this is necessary for 95% of all cable modems.
What you can do to resolve this problem for the future is to buy a router, which will ALWAYS be connected to the cable modem.  You can connect devices all day long to the back of the router and you should be fine.  Just don't forget to power down the modem when you connect the router for the first time.


Sorry for the late response on this one. I will work on the solutions provided as soon as possible. Thank you.
Ok, so I finally fixed the problem. I plugged in a totally different laptop directly to my cable modem and it worked for some reason. I had an internet connection when directly connected to my cable modem. Then I tried hooking up my D-Link wireless router and of course I had no internet connectivity as I expected. I went into the router's admin web page, looked around, and noticed that my router was set to PPPoE per my previous DSL settings. I changed this to DHCP and rebooted the router. I now have cable Internet connectivity.

Thanks for the tips folks. Each one brought me closer to this solution.

No objection.


I tried this solution and it worked perfectly.