您是否曾经在朋友家连接到无线网络(wireless network)，但即使您已连接也无法访问互联网？(Internet)Windows 是否(Did Windows)告诉您无法访问 Internet(Internet access)？如果答案是肯定的，请阅读本文以了解如何解决和解决此问题。
如何判断您是否无法访问互联网(Internet Access)
第一个标志是Windows直接显示的：任务栏中的无线连接图标(wireless connection icon)上有一个黄色的感叹号(exclamation mark)。如果您将鼠标放在它上面或单击它，Windows会说它无法访问 Internet(Internet access)。在Windows(Windows 7) 7、8.1 和 10 上，此图标出现在同一位置 - 时钟附近，屏幕右下角。
在Windows 10上，图标看起来有点不同，但它在同一个地方，所以你不能错过它。
无法访问Internet(Internet access)的另一个明显迹象是无法在浏览器中访问网站。访问网站根本不起作用。
互联网连接(Internet Connection)故障排除
让我们看看如何解决这个问题。Windows(Windows 7) 7、8.1 和 10的故障排除步骤基本相同：出于本文的目的，我们使用了在Windows 10中截取的屏幕截图。要进行故障排除，请使用Internet 连接(Internet Connections)故障排除向导。要了解故障排除向导是什么、如何访问它们并开始使用它们，请查看本教程：如何排除网络和 Internet 问题(Troubleshoot Network & Internet Problems)。
从网络和 Internet(Network and Internet)故障排除向导列表中，选择Internet 连接(Internet Connections)。
在按下Next之前，单击或点击Advanced链接。
有一个选项显示“自动应用修复”("Apply repairs automatically")。选中该选项，然后单击(option and click)或点击Next。
几秒钟后，向导会询问您要解决什么问题。选择“解决我的 Internet 连接问题”("Troubleshoot my connection to the Internet")。
向导现在开始寻找问题及其可能的根本原因。等到(Wait)它完成。时间不应超过一分钟。
当向导完成其检测工作时，它会显示其发现的摘要。在我们的例子中，它说：“DNS 服务器没有响应”("The DNS server isn't responding")。
在较早的情况下，疑难解答程序有不同的结果：它说“安全或防火墙设置可能会阻止连接”("Security or firewall settings might be blocking the connection")。
注意：(NOTE:)当您注意到没有Internet 连接(Internet connectivity)时，启动Internet 连接(Internet Connections)疑难解答的最快方法是右键单击或点击(click or tap)并按住任务栏中带有感叹号(exclamation mark)的图标，然后选择疑难解答(Troubleshoot problems)。这将在启用“自动应用修复”("Apply repairs automatically")设置的情况下自动启动疑难解答。
如何解释问题并解决(Problem & Fix)它？
一切都很好，但是……接下来呢？向导所说的只是您有问题并且没有明显的解决方案。你已经知道了，对吧？
这里有几件事可能会导致问题：您计算机的防火墙及其设置，或者控制您所连接的无线网络(wireless network)的路由器的防火墙和安全设置。(firewall and security settings)
首先，检查简单的部分：您自己计算机的防火墙。它是否有任何奇怪的设置阻止您与Internet的连接？如果在其他无线网络上一切正常，并且在连接到新的(wireless network)无线网络(wireless network)时您没有更改任何设置，那么很可能这不是问题的根源。
第二个也是更可能的问题是管理无线网络(wireless network)的路由器。向网络所有者询问他或她在路由器上配置的任何特殊设置。路由器是否根据某些特定规则阻止访问？
我问我的朋友，我在谁的网络上遇到了这个问题，他笑着告诉我，他正在路由器上使用MAC 过滤(MAC filtering)，以阻止不受欢迎的访客使用他的Internet连接。这是什么意思？简而言之(Simply)，只有拥有经过批准的MAC 地址(MAC address)的计算机才能使用他的无线连接(wireless connection)。因此，他需要批准我电脑的MAC，这样我才能在连接到他的无线网络时(wireless network)上网(Internet access)。
其他原因可能是DNS 服务器(DNS server)已关闭 - 如果是这种情况，您可能需要要求网络管理员配置网络可以在这种情况下使用的第二个或第三个DNS 服务器。(DNS server)
结论
当您遇到Internet 连接(Internet connection)问题时，原因可能很复杂。如果您正在调查此类问题，请确保找到问题的根源：尝试连接到不同的网络并尝试(network and try)使用不同的设备连接到同一网络。此测试将让您知道您的设备或您使用的网络是否存在问题。如果您对解决Internet 连接(Internet connection)问题有任何其他提示，请在评论中告诉我们。您可以随时通过分享这篇文章来检查您是否仍然连接到互联网！(Internet)
Troubleshoot Internet Connection Problems Over A Wireless Network
Have you ever connected to a wireless network at a friend's house and could not acсess the Internet, eνen though you were connected? Did Windows tell yoυ that there is no Internet access? If the answer is yes, then read this article to find out how to troυblеshoot and fix this issue.
How To Tell If You Don't Have Internet Access
The first sign is shown directly by Windows: the wireless connection icon in the taskbar has a yellow exclamation mark on it. If you keep your mouse over it or click on it, Windows will say it has no Internet access. This icon appears in the same place - nearby the clock, in the bottom right corner of the screen - on Windows 7, 8.1 and 10.
On Windows 10, the icon looks a little bit different, but it's at the same place, so you can't miss it.
Another obvious sign of no Internet access is being unable to visit websites in your browser. Accessing websites simply does not work.
Troubleshooting The Internet Connection
Let's see how to get this fixed. The troubleshooting steps are basically the same for Windows 7, 8.1 and 10: for the purpose of this article, we used screenshots taken in Windows 10. For troubleshooting, use the Internet Connections troubleshooting wizard. To learn what troubleshooting wizards are, how to access them and get them started, check out this tutorial: How to Troubleshoot Network & Internet Problems.
From the list of Network and Internet troubleshooting wizards, select Internet Connections.
Before you press Next, click or tap on the Advanced link.
There is an option which says "Apply repairs automatically". Check that option and click or tap Next.
After a few seconds, the wizard asks what you want to troubleshoot. Select "Troubleshoot my connection to the Internet".
The wizard now starts looking for problems and their possible root-causes. Wait until it finishes. It should not take longer than a minute.
When the wizard completes its detective job, it shows a summary of its findings. In our case, it says: "The DNS server isn't responding".
On an earlier occasion, the troubleshooter had a different result: it said "Security or firewall settings might be blocking the connection".
NOTE: When you notice there is no Internet connectivity, the fastest way to start the Internet Connections troubleshooter is to right click or tap and hold on the icon with the exclamation mark from the taskbar, and select Troubleshoot problems. This will automatically start the troubleshooter with the "Apply repairs automatically" setting enabled.
How To Interpret The Problem & Fix It?
All fine and dandy but... what next? All the wizard says is that you have a problem and no apparent solution. You knew this already, right?
There are a couple of things that can cause issues here: your computer's firewall and its settings or the firewall and security settings of the router that controls the wireless network to which you are connected.
First, check the easy part: your own computer's firewall. Does it have any weird settings that block your connection to the Internet? If things worked correctly with other wireless networks and you have not changed any settings when connecting to the new wireless network then, most probably, this is not the source of the problem.
The second and more likely problem is the router which manages the wireless network. Ask the owner of the network about any special settings he or she configured on the router. Is the router blocking access based on some specific rules?
I asked my friend, on whose network I had this issue and he told me with a smile that he is using MAC filtering on his router, to block unwanted guests from using his connection to the Internet. What does it mean? Simply put, only computers with an approved MAC address can use his wireless connection. Therefore, he needed to approve my computer's MAC, so that I can get Internet access when connecting to his wireless network.
Other reasons can be that the DNS server is down - if this is the case, you might want to ask the network's administrator to configure a second or third DNS server that the network can use in such cases.
Conclusion
When you are experiencing Internet connection problems, the reasons can be complicated. If you're investigating such problems, make sure to get to the root of the problem: try connecting to a different network and try to connect to the same network with a different device. This test will let you know whether there is a problem with your device or the network you are using. If you have any additional tips on troubleshooting Internet connection problems, let us know in the comments. And you can always check if you're still connected to the Internet by sharing this article!
