Troubleshoot problems finding wireless networks

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 Picture of 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:

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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 or access point.

With 802.11b or 802.11g routers and access points, the maximum range is up to 150 feet (46 meters) indoors and 300 feet (92 meters) outdoors. With 802.11a routers and access points, the maximum range is 50 feet (15 meters) indoors and 100 feet (30 meters) 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 or access point. 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 or access point, 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 or access point is turned off or is not working properly.

There are two things to try:

  • Make sure the router or access point is turned on and that the wireless signal light is illuminated.

  • Reset the router or access point by turning it off, waiting at least 10 seconds, and then turning it back on.

    Warning

    • Resetting the router or access point 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. Other cordless phones use the 5 GHz frequency, which is used by 802.11a 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 or access point 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. In the United States and Canada, you can use channels 1, 6, and 11. Check the information that came with your access point or router for instructions about setting the wireless signal channel.

Windows is not configured to connect to the right type of network.

Check the information that came with the router or access point to find out what connection mode the device is set to. The mode should be 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 this network matches the setting on the device. To check this, follow these steps:

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

  2. Type netsh wlan add filter networktype=network type.

    Where network type is either adhoc or infrastructure.

The router or access point is busy.

The router or access point 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 and access points can be set up so that they don't broadcast the network name. In this case, you can't 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 Picture of 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.

Your network administrator is blocking access to certain networks.

If you are on a corporate network, your network administrator might be using Group Policy to control your access to wireless networks. If you think there are wireless networks in range of your computer that are not visible or that you cannot connect to because your network administrator has blocked access to them, contact your network administrator for assistance.

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.