After Henry switched internet service providers, two of his PCs can no longer connect to Wi-Fi. What can he do?
I recently changed my internet service from BT to TalkTalk. I have lost Wi-Fi on my Fujitsu Esprimo V5535 and my Acer Revo, but my tablet and another laptop both connect.
Henry
Wireless networking is a huge can of worms, most of which have been hidden away. First, there was the Wi-Fi Alliance, which not only set interoperability requirements but made suppliers test them. Second, companies developed software to connect PCs, smartphones and tablets to these standardised Wi-Fi networks more or less automatically. One example was the Wireless Zero Configuration (WZC) utility added to Microsoft Windows XP. As a result, Wi-Fi usually works, except when it doesn't.
The first thing to try with both your machines is the built-in Windows troubleshooter, which usually fixes the problem, in my experience. The troubleshooter should pop up when Internet Explorer fails to make a connection, so you can just click the button that says "Diagnose Connection Problems". Otherwise, right-click the internet icon in the SysTray on the bottom right of the Task Bar (next to the clock) and select Troubleshoot Problems.
There are several other ways to run the Windows Network Diagnostics in Windows 7. For example, you can open the Control Panel's Network and Sharing Center, or go to the Start button in, type network in the search box, and select "Identify and repair network problems". For Windows XP users, Microsoft has an online guide: How to troubleshoot home networking in Windows XP, but XP's Home and Small Office Networking Troubleshooter works in much the same way.
You can also try the networking equivalent of turning it off and on again. Go to the Network and Sharing Center and click "Manage wireless networks". Right-click on your wireless network and select "Remove network" from the drop-down list. Next, go back to the Network and Sharing Center, click "Connect to a network" and add your own Wi-Fi network.
If neither of those works, you can try the update and reboot route below. Ideally, keep a log of everything you try, in case you need to call in outside help.
Update and reboot
To begin, plug your Fujitsu laptop and Revo nettop into the mains and make sure the Power Options setting is on Maximum Performance. (To be specific, we don't want the Wireless Adapter Settings to be in Power Saving Mode where they might turn themselves off.) You should now be able to connect your Fujitsu laptop and Revo nettop to the internet via standard Ethernet cables.
When you get online, run Windows Update to get Windows up to date with essential (but not optional) updates. After that, check each manufacturer's website to see if they have any more recent drivers than the ones you have installed. If they do, use the Device Manager to update them. While you're at it, check to see if there are any firmware updates for whichever router TalkTalk has supplied, though generally I'd leave installing this until it's the next-to-last resort. (The last resort is re-installing Windows.)
As far as I know, TalkTalk is still using the IPv4 Internet Protocol not IPv6, so you may want to make sure all your devices either support both or only use IPv4. Microsoft has a support page, How to disable IPv6 or its components in Windows, where you can disable or re-enable IPv6 simply by clicking a "Fix it" button.
With everything up-to-date, shut all your devices down, and turn off the power on your router for one minute. (If it is one of those rare models with a built-in battery, you will have to find and press the re-set button.) Once the router has come back up and reconnected, turn on your devices one at a time and see if they connect. The router acts as a NAT (Network Address Translation) router, which uses one internet (IP) address to talk to the public internet, but gives each of your devices its own private address, usually in the format 192.168.x.x. Obviously, each device must be assigned its own separate address, so as to avoid conflicts. If your Esprimo and Revo are both trying to use the same address, probably neither will work.
At this point, all your devices should connect correctly. If one doesn't, double-check that it is set to use DHCP (Dynamic Host Configuration Protocol) rather than a static IP address. With this approach, the device asks the router for an address and the router provides one. More accurately, it gives your PC a renewable lease on a specific address, which may last for a week or so.
Using commands
If you don't mind peeking inside the can of worms, you can check the IP configuration and force its renewal to one that, we hope, will work. To do this, open a command prompt (aka terminal window or "DOS box") by going to the Run box -- for example, press Windows Key+R -- typing cmd and clicking OK. This will run the cmd.exe program. At the command prompt, type ipconfig /all (there is one space after ipconfig) and check the result. It should say DHCP Enabled, Autoconfiguration Enabled, IPv4 Address Preferred, and give you the dates for Lease Obtained and Lease Expires.
Now you can force your Windows PC to refresh its IP configuration by going to the command prompt and typing ipconfig /release and pressing Enter, then ipconfig /renew and pressing Enter. If that doesn't work, you can re-set the whole TCP/IP stack back to its original state by using the NetShell utility, netsh, and try again. You don't need to learn NetShell commands because there's a "Fix it" button at How to reset Internet Protocol (TCP/IP).
There are a few other things that can mess up a Wi-Fi connection, but they're not usually problems for home users. Sometimes there are problems with network adaptors, but the Troubleshooter should catch them. If not, see How do I fix network adapter problems? Sometimes Wake-on-LAN (WOL) causes problems in PCs that are designed to be turned on remotely by a "magic packet" instead of responding to DHCP. This seems unlikely in your case.
You don't say if you have contacted TalkTalk for help, but if your Esprimo and Revo are still not connecting, then you can check the Support FAQ and post your problem in the TalkTalk Community forum. I notice there's a long list of "known issues" with the Huawei HG533 router, for example. This is the kind of thing that eventually drives people to install their own routers….
Posted on Fri, 31 Jan 2014 09:16:00 GMT at http://www.theguardian.com/technology/20...-new-hi-fi