Sometimes a device simply won't connect to a wireless router because of an improper start-up sequence. Restarting your device may fix this problem., If your wireless router kicked your device off of the network, it may be because of a few different reasons:


The wireless Internet's password was changed - Select the wireless network and enter the updated password.

The device is not up to date - Update your device to the minimum required version.

The router was reset - Use the router's stock password to connect. The stock password (also known as the "security/network key") is usually on the back or bottom of the router.
 Causing your computer or phone to "Forget" the Wi-Fi network's settings will clear up any connection conflicts. To do so:


iPhone - Open Settings, tap Wi-Fi, tap a network, and tap Forget This Network at the top of the page.

Android - Open Settings, tap Connections (Samsung devices), tap Wi-Fi, tap a network, and tap Forget.

Windows - Open Settings, click Network & Internet, click Wi-Fi, click Manage known networks, click a network name, and click Forget.

Mac - Click the Wi-Fi symbol, click Open Network Preferences, click the Wi-Fi tab, click Advanced, click a network's name, and click -.
 You can do this by finding the "Reset" button, which is usually a tiny hole on the back of the router, and pressing it with a bent paperclip for ten seconds. Once you reset your router, you'll be able to reconnect using the router's stock password and network name., If you can connect to a coffee shop's or school's Wi-Fi but can't connect to your own, the problem is likely with your router or connection, not your device., If your router or connection is the problem, you'll need to call and request a network test or a replacement router and modem (if you rent equipment from your ISP).
Restart your devices.
Determine why your device won't automatically connect.
"Forget" the connection on your device.
Reset the router to factory settings.
Try connecting to a different network.
Call your service provider's Customer Support hotline.
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