One device can’t connect to the Wi-Fi #
Sometimes you run into an issue with one particular device. It’s probably just a momentary issue. Try turning off the Wi-Fi on your device, then re-enabling it. If that doesn’t work, do the same with your router by unplugging it and then plugging it back in 30 seconds later.
If that doesn’t help, or if the problem reoccurs, consider deleting your current network from the list of saved networks on your device, then reconnect again.
If you’re running Windows 10, search for “wifi troubleshooting” and open the result, which should be Identify and Repair Network Issues. That will go through a series of diagnostics that may restore connectivity. On MacOS, you can run Wireless Diagnostics. Hold the Options key and click the AirPort (Wi-Fi) icon on the menu bar. Find Open Wireless Diagnostics, and then follow the on-screen instructions.
If none of that works, consider rebooting the device. Log into your Wi-Fi app or administrator settings (which you can find by searching your IP address on your browser — here’s how to find it). Look for a list of currently connected devices and pinpoint the devices you don’t recognize. First, make sure these don’t represent connections you didn’t realize you had — each smart device will have its own connection, for example, and they can have some strange titles if you didn’t name them. Game consoles and TVs may also be connected.
If you’ve ruled out all your own potential devices and there’s still a connection or two you don’t recognize, it’s possible someone else is hijacking your Wi-Fi network. In this case, look in your settings for an option to block these devices on your Wi-Fi, and ban their MAC addresses if possible. Then change your Wi-Fi password, and reboot your router (here’s how). This may not stop especially determined hackers, but it’s usually enough to kick unwanted guests off your network.