Before calling for technical support, here are a few steps to try that can help to re-establish your Internet connection.
The first thing you should ensure is that all your devices are properly connected. Check that the power for the modem is on and if you have any hubs or firewall devices, make sure they have power as well. Next check to make sure that the Ethernet cable is securely plugged into the computer and modem.
If you have firewall or proxy software, ensure that it is properly configured. You may want to disable it to see if it is interfering with your connectivity.
Sometimes Windows will have an internal error that causes network connections (which is what the Internet is) to stop functioning. Restarting your computer can resolve this issue.
If you still have no connection, continue to step # 3.
Choose your operating system:
As a last resort, if you still have no connection, try step # 4.
The Cable Modem can occasionally lose its connection due to an internal error. This is rare but can happen. If the above steps have been tried with no success, try the following.
If you still cannot achieve connectivity it may be a system wide issue or perhaps a network configuration problem on your system.