Fix iOS 11.4 Wi-Fi Issues: Step-by-Step Guide

If your iPhone or iPad running iOS 11.4 keeps dropping Wi-Fi, connects but has no internet, or shows a weak signal, the fixes below usually solve it. Start with the quickest and least disruptive steps—forgetting the network, resetting network settings, and checking router compatibility—before considering a restore or DFU mode.

Why iOS 11.4 Wi-Fi Problems Happen

iOS 11.4, released in May 2018, introduced several changes to how devices handle Wi-Fi and Bluetooth. Some users reported that the update caused their devices to forget networks, connect to the wrong band (2.4 GHz vs 5 GHz), or fail to obtain a valid IP address. In many cases, the issue is not a hardware fault but a software conflict between the device’s saved network data and the router’s settings. Common triggers include:

Corrupted network preference files left over from previous iOS versions.
Router firmware that is incompatible with iOS 11.4’s Wi-Fi standards (802.11k/v/r roaming).
Channel congestion or interference from neighboring networks.
Battery saver or low power mode interfering with background Wi-Fi scans.

Quick Fixes to Try First

Before doing anything drastic, try these simple steps. They take less than a minute and often resolve the issue:

Toggle Wi-Fi off and on: Open Settings > Wi-Fi, turn the switch off, wait 10 seconds, then turn it back on.
Restart your iPhone: Press and hold the side button and either volume button until the slider appears. Slide to power off, wait 30 seconds, then turn it back on.
Restart your router: Unplug the power cord, wait 15 seconds, plug it back in, and wait for the lights to stabilize.
Forget and rejoin the network: Go to Settings > Wi-Fi, tap the “i” next to your network, choose “Forget This Network,” then re-enter the password.

If these don’t help, move to the more involved fixes below.

Reset Network Settings

Resetting network settings clears all saved Wi-Fi passwords, Bluetooth pairings, and cellular settings. It does not delete your photos, apps, or other data. This is a common fix for Wi-Fi issues after an iOS update.

Go to Settings > General > Reset.
Tap Reset Network Settings.
Enter your passcode if prompted, and confirm.
Your device will restart. After it boots, go to Settings > Wi-Fi and reconnect to your network.

You’ll need to re-enter Wi-Fi passwords and re-pair Bluetooth devices. This often clears the corrupted network preferences that cause iOS 11.4 Wi-Fi problems.

Adjust Router Settings for Better Compatibility

iOS 11.4 devices sometimes have trouble with routers that use certain security or channel settings. Try these router-side adjustments:

Change Wi-Fi security to WPA2-PSK (AES): Avoid WEP or WPA/WPA2 mixed modes, which can cause connection drops.
Set the channel to a fixed value: Instead of “Auto,” choose a specific channel (e.g., 1, 6, or 11 for 2.4 GHz). This reduces interference.
Disable 802.11r fast roaming: Some routers have this enabled by default; it can cause iOS devices to disconnect when moving between access points.
Update router firmware: Check the manufacturer’s website for the latest version.
Split the 2.4 GHz and 5 GHz bands: Give them different names (SSIDs) so your iPhone connects to the stronger one consistently.

When to Restore via iTunes or Finder

If network reset and router changes don’t work, a full restore may be necessary. This erases your device and reinstalls iOS, which can fix deeper software corruption. Back up your device first via iCloud or a computer.

Connect your iPhone to a computer with iTunes (Windows or macOS Mojave and earlier) or Finder (macOS Catalina and later).
Select your device when it appears.
Choose Restore iPhone and confirm. This downloads iOS and installs it fresh.
After the restore, set up as new or restore from your backup.

If a standard restore doesn’t help, you can try DFU (Device Firmware Update) mode, which is a deeper restore. To enter DFU mode on iPhone 7 and later: connect to a computer, press and hold the side button and volume down for 10 seconds, then release the side button but keep holding volume down for 5 more seconds. The screen stays black, and iTunes/Finder will prompt you to restore.

Common Misconceptions and Pitfalls

Many users think that resetting network settings will delete all their data—it doesn’t. Others assume that a weak signal is the router’s fault, but sometimes it’s the iPhone’s Wi-Fi antenna. However, if you’ve tried all software fixes and the problem persists, it could be a hardware issue. In that case, contact Apple Support or visit an Apple Store for diagnostics.

Another misconception is that iOS 11.4 Wi-Fi issues are caused by the device overheating. While heat can affect performance, it rarely causes Wi-Fi drops. Also, turning off Wi-Fi Assist (Settings > Cellular > Wi-Fi Assist) can prevent the phone from automatically switching to cellular data when Wi-Fi is weak, which might mask the problem.

Alternatives: Use a Different Wi-Fi Band or Ethernet

If your router broadcasts both 2.4 GHz and 5 GHz, try connecting to the 5 GHz band for faster speeds and less interference. However, 5 GHz has shorter range. If you’re far from the router, 2.4 GHz might be more stable. You can also use an Ethernet adapter (Lightning to USB 3 Camera Adapter) to connect directly to the router for a wired connection, though this is not a permanent solution for most users.

Frequently Asked Questions

Q: Will I lose my photos if I reset network settings?
No. Resetting network settings only clears Wi-Fi passwords, Bluetooth connections, and cellular settings. Your photos, apps, and other data remain untouched.

Q: Why does my iPhone say “Incorrect Password” even though the password is correct?
This often happens after an iOS update. Try forgetting the network and re-entering the password. If that fails, restart the router and try again.

Q: Can I downgrade from iOS 11.4 to an older version?
Apple stops signing older iOS versions shortly after a new release. As of now, you cannot downgrade to iOS 11.3 or earlier because Apple no longer signs those versions. Your only option is to update to the latest iOS.

Q: Does turning off Wi-Fi Assist help with Wi-Fi issues?
Wi-Fi Assist automatically uses cellular data when Wi-Fi is weak. If you’re seeing slow speeds, turning it off can prevent the phone from switching, but it won’t fix the Wi-Fi connection itself.

Q: Will a factory reset fix Wi-Fi issues?
Yes, a factory reset (erase all content and settings) can fix persistent software problems. It’s more thorough than a network reset, but you’ll need to restore from a backup to get your data back.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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