Windows Vista: Troubleshoot problems finding wireless networks

Published 21/05/2004 16:09   |    Updated 02/05/2008 11:49
I am using Windows Vista and I cannot detect my wireless network. What can I do?


A wireless network adapter is a device that connects your computer to a network, it is sometimes referred to as a network interface card (NIC). If your computer has a wireless network adapter, Windows will automatically detect wireless networks in range of your computer. You can see a list of wireless networks that Windows has detected in Connect to a Network.


Open Connect to a Network by clicking the Start button and then clicking Connect to.


If Windows does not detect a network that you think is in range of your computer, it could be because of one the following reasons:



The wireless switch on your computer is turned off.
Many mobile PCs have a wireless switch on the front or side of the computer. Check your computer for a switch. If you do have a switch, make sure it's turned on. Some computers also use a function key combination to turn the switch on or off. Check the information that came with your computer for details on locating the wireless switch.


Your computer is too far from the wireless router.
With 802.11b or 802.11g routers, such as the BT Voyager 2110, the maximum range is up to 50 meters (164 feet) indoors and 100 meters (328 feet)  outdoors. These ranges are in optimal conditions with no interference. Make sure that your computer is within this range and as close as possible to the router. If the computer is portable, try moving it around to determine the range of the wireless signal and the best place to put the computer.


If you are unable to get closer to the router, you might want to consider buying and installing an external antenna to your wireless network adapter. Many wireless network adapters are set up so that you can attach an external antenna to them, which will provide you with better reception than the built-in antenna. Check the information that came with your wireless network adapter to see if you can install an additional antenna.


The wireless router is turned off or is not working properly.
There are two things to try:

  • Make sure the router is turned on and that the wireless signal light is illuminated.
  • Powercycle the router by turning it off, waiting at least 10 seconds and then turning it back on.  

Note: Resetting the router will temporarily disconnect everyone from the network. If you don't manage the access point or network, contact the network administrator.


There is interference from other devices.
Some home devices can cause interference between your computer and networks that might be in range. For example, microwave ovens and some cordless phones use the 2.4 gigahertz (GHz) frequency, which is also used by 802.11b and 802.11g network hardware.


There are two things you can try in this situation:

  • If any devices like these are near your computer, turn them off temporarily or move them farther away.
  • Change the router settings to use a different wireless channel, or set the channel to be selected automatically if it is set to a fixed channel number. Sometimes, one wireless channel is clearer than others. Click here for instructions about changing the wireless signal channel  on a BT supplied router.



Windows is not configured to connect to the right type of network.
There are two types of connection mode a wireless router can be set to: either ad hoc (when devices communicate directly without going through a router or access point) or infrastructure (when devices communicate by going through a router or access point). Make sure the setting in Windows for your BT wireless  network is set to infrastructure mode. To check this, follow these steps: 

  1. Open the Command Prompt window by clicking the Start button, clicking All Programs, clicking Accessories, and then clicking Command Prompt.

  2. Type netsh wlan add filter infrastructure=infrastructure.



The router is busy.
The router might be too busy to respond to new requests if there are several computers or devices using it. If you have other computers that are connecting to the network, try temporarily disconnecting them.


The network you are looking for is set to not broadcast its network name (SSID).
Wireless routers can be set up so that they do not broadcast the network name. By default, all BT supplied routers are set to broadcast their SSID. If you cannot detect that the network is in range (in order to connect to it) unless you have previously connected to the network or you manually connect to the network using the service set identifier (SSID). To connect to a network that is not broadcasting, follow these steps: 

  1. Open Connect to a Network by clicking the Start button and then clicking Connect to.
  2. Click Set up a connection or network.
  3. Click Manually connect to a wireless network and then type the network information.

    The network will be added to your list of networks and will be available to connect to in the future when your computer is in range of the network.


The wireless network adapter is in monitor mode.
If a network monitoring program is running on your computer, the wireless network adapter will be set to monitor mode, which prevents Windows from connecting to wireless networks. To connect to a wireless network, close the network monitoring program or follow the instructions in the program to exit monitor mode.



See also: What can I do to improve the wireless range between my wireless router and computers?



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