This method is hardly a cure-all, however, and that's why I direct you next to the Assist Me button at the bottom of the window. Click it and a sheet appears. Within this sheet, click Diagnostics. This launches the Network Diagnostics application that helps you determine the health of your network.
The left side of the window displays a series of entries. For an ethernet connection, you'll see Ethernet, Network Settings, ISP, Internet, and Server. For a Wi-Fi connection, you'll see Wi-Fi, Wi-Fi Settings, Network Settings, ISP, Internet, and Server. When you have a solid Internet connection, a green dot will appear next to each item. If something's wrong, you'll see red dots. If Ethernet, Network Settings, and ISP bear the green dot, but the Internet entry has a red dot next to it, the problem is on your IPS's end and not yours. Wait it out or contact your ISP to find out when the issue will be fixed. If the red dots appear next to Ethernet and Network Settings, there's something wrong with your network configuration.
If the problem appears to be on your end, you may be able to fix it by simply choosing the kind of connection you're using and clicking through a series of Continue buttons. Network Diagnostics can repair a handful of local network issues, so click Continue a few times to see what it can do.
About the Wi-Fi menu
If you're using a Wi-Fi network, it's worth your while to enable the Show Wi-Fi Status in Menu Bar option in the Network system preference. Do this and you can easily turn off Wi-Fi by choosing the Turn Wi-Fi Off command. Also, a helpful fan icon appears in the Mac's menu bar. The number of black bars in that fan indicates the wireless network's signal strength. If you see just one or two black bars, try moving closer to the wireless hotspot to increase the signal strength, as a poor signal can mean a slower connection.
But the Turn Wi-Fi Off command and the fan icon aren't the only reasons to enable the Wi-Fi menu-bar option. You'll also see many nearby wireless networks. Those that bear just a fan are open and those with a lock icon next to them require that you know the password to join the network.
Note: Not all open networks truly are. If you've spent time with a laptop or iOS device in an airport, convention center, or hotel, you've likely seen entries for Free Public Wi-Fi networks. These aren't real open networks. Rather, they're the result of a bug in Windows XP. When a computer running XP can't find a recognized Wi-Fi network, it creates an ad-hoc network of its own and broadcasts itself as Free Public Wi-Fi. If you try to connect to it, you'll discover that no Internet connection results. It's not dangerous to do this--your Mac won't get cooties--but in terms of actually getting on the Internet, it does you no good whatsoever.
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