OS X Mavericks: Solve problems with connecting to the Internet
If you can’t connect to the Internet, there may be a problem with your cables, your devices, your network settings, or your ISP.
Use Network Diagnostics
If you experience trouble with a network connection you have already set up, use Network Diagnostics to diagnose and resolve the problem.
Check your AirPort connection
If you’re using an AirPort wireless network, make sure your computer is communicating with the AirPort Base Station and that the base station is connected to the Internet.
For more information on connecting to the Internet using AirPort, open AirPort Utility, then choose Help > AirPort Utility Help.
Check your cables
Make sure all cables are properly connected. If you’re using an external modem, be sure one cable firmly connects the modem to your computer, and another connects the modem to a working wall jack.
Check external devices
Check that all external devices such as external modems, hubs, and routers are plugged in, turned on, and have started up completely. Try resetting these devices by unplugging them for a couple of minutes and then plugging them back in.
Check the indicator lights on the modem to see whether the modem is registering a connection to the network and to your computer. If an indicator light does not come on, refer to the documentation that came with your modem or contact your ISP.
Check your settings
Make sure you are using the proper network settings for your type of Internet connection. Open the Network pane of System Preferences and check the status of each network service, such as Ethernet, Bluetooth, and AirPort. The network service you are using should have a green indicator and the word “Connected.”
To view more information about your network service, click to highlight it. For additional help, click the “Assist me” button.