To fix an iPhone 7 that keeps getting Wi-Fi error after updating to iOS 11:
- You won't get a signal if you're too far away from your Wi-Fi router, so be sure you're within range.
- Make sure Wi-Fi is turned on under Settings > Wi-Fi. To join, tap the name of your Wi-Fi network. You're connected if you see a blue checkmark next to a network name.
- If Auto Join Disabled appears next to your Wi-Fi network name, tap it to enable Auto-Join.
- If prompted, provide your Wi-Fi network's password. You may receive a 'unable to join the network' or 'incorrect password' notice even though you input the correct password. Try entering your password again after restarting all of your devices.
- You might notice a Wi-Fi recommendation under the name of the Wi-Fi network you're connected to if iOS or iPadOS detects a problem with your Wi-Fi connection.
- If you still can't connect to your network or get online, double-check that your router is turned on and linked to your modem.
- Restarting your iOS or iPadOS device may help.
- Then reboot your router as well as your cable or DSL modem. Unplug and then re-plug your router or modem to restart it.
- Tap Settings > General > Reset > Reset Network Settings if you're on iOS or iPadOS 14 or earlier. This also resets any previously used Wi-Fi networks and passwords, cellular settings, and VPN and APN settings.
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