Do you mean your WiFi is not working? If so, log on to the router via an Ethernet connection and check the wireless settings - network name, pass phrase, wireless channel, protocol and encryption mode. Check that the wireless is still enabled and that the SSID (network name is not hidden). Also check that MAC...
Best answer: Do you mean your WiFi is not working? If so, log on to the router via an Ethernet connection and check the wireless settings - network name, pass phrase, wireless channel, protocol and encryption mode. Check that the wireless is still enabled and that the SSID (network name is not hidden). Also check that MAC address filtering has not been turned on. If somebody has changed any of these settings, then either you will have to make corresponding changes in your WiFi devices, or you will have to set them back to the proper settings.
If the SSID has changed, you can set up a new WiFi profile on your devices. The old network name will no longer show on your devices.
If the pass phrase has changed, devices will normally report this and ask for the correct pass phrase.
If the channel has changed, it may now be on a channel that your device does not support. This is probably most common on 2.4 GHz if the router is using channels 12, 13 or 14. Devices in the USA only use channels 1 to 11 and sometimes are unable to see channels 12 to 14.
If the protocol has been restricted say from 802.11b/g/n to 802.11n only, then devices relying on the other protocol will not work.
If the encryption mode has changed, the device will normally ask for a pass phrase to be entered for the new mode.
Obviously the wireless network may be disabled, and it needs to be enabled for wireless connection.
If the SSID broadcast was enabled and has been disabled, then the device has to be set to connect even when the SSID is not broadcast. There is little point in disabling SSID broadcast as it has almost no effect on network security and can meaan that nearby networks may use the same wireless channel, which will interfere with your network, as they will not know your network is there but hidden.
If MAC address filtering is on and your device is not permitted through the filter, then the network will not be available to you.
I have seen one router (a BT Hub 4) that lost 2.4 GHz and required the router to be factory reset using the reset button. Other routers may have a similar issue.
When asking a question like this one, it helps if you include all the symptoms and the make and model of device you are asking about. There are hundreds of different routers, and simply saying the lights are green is not very helpful.
Finally, if you can connect to the router itself, but cannot reach the Internet then the wireless adapter in the router is working. Do WiFi connected devices get their proper addresses? Can you log on to the router's configuration settings over WiFi?
Back to you for some diagnosis.
I hope this helps.
19 hours ago