While upgrading to iOS 18, if you get a pop-up saying “Software Update Failed. An error occurred downloading iOS 18” on your iPhone, don’t panic. You can try a couple of solutions that have helped many users across the globe to come out of the situation. Here you will learn the 7 most trusted and proven fixes if your iPhone shows the software update failed error.
How to Fix Software Update Failed Error During iOS 18 Update
You can go through the following list and try each troubleshooting method to isolate and fix your iPhone if the iOS 18 software update fails.
Solution 1: Delete the Old Update File
If your iPhone already downloaded other versions of iOS before but for some reason, you didn’t install it, they hinder your iPhone from updating to iOS 18 because your iPhone may think you’ve already had a software file to install, so it fails to download iOS 18. In this situation, you can delete the software file from your phone’s storage, re-download the latest software, and then try again. The guide to getting rid of the corrupt update is explained below.
- On your iPhone, go to Settings.
- Tap General.
- Tap iPhone Storage.
- From the iPhone Storage screen, scroll down and tap the iOS 18 update entry.
- Tap Delete Update from the next window that appears.
- Confirm your action if your iPhone prompts you to permanently remove the corrupt update file from your device’s storage.
- Try upgrading to iOS 18 again and see if the issue got fixed.
Solution 2: Check Your iPhone Storage
iOS 18 requires at least 6 GB to 8 GB of free storage to install successfully. If your phone doesn’t have the said space to accommodate the newer version of the OS, you may see the iPhone software update failed error.
You can follow the instructions given below to check the amount of free space your device has, and if the storage is insufficient, you can learn how to free up some of it in the easiest possible manner as well:
To Check the Storage
- Go to Settings.
- Tap General.
- Tap iPhone Storage.
- From the top of the iPhone Storage screen, check how much space is used. This will help you calculate the amount of free storage available on your device.
To Free Up Some Space
- If your smartphone doesn’t have enough space available, you can enable the Offload Unused Apps option by tapping Enable.
- Additionally, you can manually remove or offload the other unused apps by tapping their names individually from the list, and then tapping Offload App from the next screen.
- Once your phone has sufficient space, you can try upgrading to iOS 18 again.
Solution 3: Force Restart iPhone
If your iPhone has some glitch or its memory is occupied with some inconsistent or junk data, force restarting the phone can help. When you force restart, the flow of current is temporarily withdrawn from the motherboard and then released back, thus removing any unnecessary files and information from the iPhone’s memory that could be preventing iOS 18 installation.
However, the methods to force restart may vary depending on the iPhone models. You can learn how to force restart different iPhones here.
After force restarting, you can retry upgrading to iOS 18 and see if the problem is gone.
Solution 4: Switch to a Different Wi-Fi
Sometimes a slow wireless network may hamper the integrity of the update file that your iPhone downloads. This could be due to fluctuation in the connection, some missed or dropped data packets, or anything else. In some cases, the update file may not even get downloaded altogether due to bad Wi-Fi connectivity.
When this happens, you should try switching to a different, more consistent Wi-Fi and try upgrading to iOS 18 again. You can change a wireless network by going to WLAN or Wi-Fi on your iPhone’s Settings app, choosing another network, and entering the password.
Solution 5: Turn Off VPN
VPNs jump between several routers placed in different parts of the globe to reach the intended destination. This significantly slows down the connection speed, thus making your iPhone believe that there is some issue with the network. In addition, because of VPNs, many times the integrity of the update file is also compromised due to packet drops.
Therefore, to get rid of the issue, you can follow the steps given below that will help you turn off the VPN on your iPhone:
- Go to Settings.
- Tap General.
- Scroll down and tap VPN & Device Management.
- Tap VPN.
- Tap to turn off the Status switch on the VPN screen that opens up next.
- Try upgrading to iOS 18 again to see if the iPhone software update failed issue is gone.
Solution 6: Charge Your iPhone and Turn Off Low Power Mode
iDevices don’t update if they are not at least 50% charged and/or the ‘Low Power Mode’ is enabled. If you see the software update failed error message while upgrading your iPhone to iOS 18, you must do the following:
- Connect your iPhone to a power outlet.
- Wait until it is at least 50% charged.
- Leave the phone plugged into the power supply and continue charging it during the entire upgrade process.
- Go to Settings.
- Scroll down and tap Battery.
- Tap to turn off the Low Power Mode switch from the top of the Battery screen.
- Retry upgrading the operating system and see if the iOS 18 software update failed problem is eliminated.
Solution 7: Use iTunes to Update iPhone
If none of the above solutions help and you still see the iPhone software update failed error, you can use iTunes to download the update file on your PC and let it upgrade your phone to iOS 18. Although this method sounds a bit lengthy, the remedy works almost every time.
You can follow the procedure given below to use iTunes to upgrade your iPhone to iOS 18:
- Launch iTunes on your Windows PC (Use the Finder app if you’re a Mac user).
- Use the Lightning Cable to connect your iPhone to the computer.
- Wait while iTunes detects your iPhone.
- Click the Phone icon from the top of the iTunes’ interface.
- On the next window, make sure that the Summary option is selected under the Settings category in the left pane.
- Click Check for Update or Update from the upper section of the right window.
- Follow the on-screen instructions to initialize the process.
- Wait while iTunes upgrades your iPhone to iOS 18.
- Disconnect your phone from the computer and start using it normally.
Solution 8: The Ultimate Solution
If even iTunes cannot successfully update your iPhone, the last solution is to use a third-party tool. There are many such tools online, such as Wondershare’s Dr.Fone – System Repair (iOS). It is a tool specially designed for system problems. It is also equipped with other functions that iPhone users need, such as iOS upgrade/downgrade, which can avoid some problems that iTunes may encounter.
Conclusion
The iPhone software update failed error may come up due to any reason. If you get this message, you can try the solutions suggested above and see if any of them help. Nevertheless, before upgrading, a few things that you must ensure are that your phone is at least 50% charged, it has at least 6 GB to 8 GB of free space, and it is connected to a stable Wi-Fi network.
