Updated Oct 25,2018 | by Micky
Since the release of iOS 12 on September 17, bugs and glitches have been emerging one after another bothering iOS users. Recently, many people complain Wi-Fi doesn’t work properly after iOS 12 update.
For example, in a forum, I found some people claimed that their iPhone couldn’t connect to Wi-Fi after iOS 12 update, and after disconnecting and reconnecting, the Wi-Fi works but only lasted for a short time. Then, the problem came again.
How to resolve Wi-Fi not working after iOS 12 update? In the following paragraphs, I will provide some feasible ways I collected on the internet many of which have been proved to work out.

A recommended article you may like: How to Fix Wi-Fi Not Working on iDevices
Reset Network Settings
In the course of iOS 12 update, network settings on your device might be changed and in this case, Wi-Fi connection can be affected and doesn’t work properly.
So, if we can factory reset the network settings, making them what they were, Wi-Fi may work again on your iPhone. This method has been proved to work in most cases.
Before the following steps, remember what the local Wi-Fi’s password is because it will be removed from your iPhone’s memory.
Go to Settings > General > Reset > Reset Network Settings. Input the passcode of your device to get it done.

Check the Router
When encountering the problem of Wi-Fi not working in iOS 12, don’t panic first. Check whether your home’s Wi-Fi router works properly.
If Wi-Fi constantly drops on your iPhone or network speed is too slow, try restarting the router.
1. Shut down the router.
2. Unplug it from the power source.
3. Wait for at least 10 seconds, power on, and launch the router again.
4. Check whether the Wi-Fi works on iPhone now.
If it still doesn’t work, try finding another Wi-Fi source to have a test. If it works, then, there is something wrong with your home’s Wi-Fi.
Change the DNS Setting on iPhone
There is a more technical way to troubleshoot the issue which is changing the iPhone’s DNS setting. Try using Google DNS or Open DNS instead of the default one to see whether Wi-Fi works on your iPhone again.
1. Go to Settings > Wi-Fi.
2. Find the name of the Wi-Fi you’re using.
3. Tap on “!” beside it and you will see the internet information appear.
4. Tap on DNS and input Google or Open DNS.
Google DNS: 8.8.8.8, 8.8.4.4
Open DNS: 208.67.222.222, 208.67.220.220

Ask to Join Networks
Hardly, there are people mentioning about this way. But you might as well check whether the feature Ask to Join Networks is on.
Go to Settings > WiFi > Ask to Join Networks. Toggle it on.
Turn off WiFi Networking Service
In this way, only your location will be stopped from being used for Wi-Fi networking and it doesn’t completely block Wi-Fi services.
Go to Settings > Privacy > Location Services > System Services. Toggle off WiFi Networking and check whether it works. If so, you can turn on this feature again.
Restore Your Backup from iTunes
If none of the methods above works and meanwhile, you’ve previously backed up your iPhone via iTunes, maybe it’s time to restore your iPhone to make all settings what they were, setting the device as a new one.
1. Make sure your iTunes has been updated to the latest version.
2. Connect your iPhone to PC and launch iTunes.
3. Select your iPhone on the upper left.
4. Click on Restore Backup and choose the backup you need in terms of the date and size.
5. Click on Restore and wait until finished.
6. Keep your device connected until it restarts and the syncing process gets finished.

Bottom Line
In the above contents, I’ve introduced how to fix Wi-Fi not working after updating to iOS 12. Hopefully, your problem can be solved after trying any of those methods.
Although iOS 12 still has many bugs, as new updates keep coming out, all of them will be fixed. Be confident.
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