Fix: “An Error Occurred Installing iOS 15” on iPhone

An error occurring installing iOS 15 or above mainly happens as a result of misconfigured iPhone settings or caused by network issues. The error is not limited to a particular model of iPhone, even reported on iPads as well. The issue occurs when you try to install an iOS update to your iPhone or iPad but fails to do so, with the error message. In some cases, the problem arose when the iPhone was verifying the downloaded iOS update.

You may encounter the error occurred installing iOS 15 or above mainly due to the following reasons:

Insufficient Space on the iPhone: If your iPhone is running out of space and the iOS update does not have space to execute, then that will cause the iOS 15 or above issue.
Private Relay Feature of the iCloud: You may encounter the error under discussion if the web traffic from your iPhone is routed through the Private Relay feature of the iCloud as the data packets between your iPhone and Apple servers may get corrupt.
Network Issues: The error might occur when installing iOS 15 or above if your ISP is hindering the traffic between the Apple serves and your iPhone as the data packets may get corrupted due to the ISP interference.
Security Profiles on Your iPhone: If you have installed security profiles on your iPhone, then those may block the execution of the essential update-modules, thus an error occurred installing iOS 15 or above.

1. Perform a Force Restart of Your iPhone

A temporary glitch in the iPhone’s modules may not let you update it to iOS 15 or above (like 15.5 currently). Here, performing a force restart of your iPhone may clear the updating problem. But before proceeding, make sure your iPhone is compatible with the latest iOS 15 or above as not every iPhone will be able to update to iOS or above. Moreover, it is worth mentioning that this article is written for an iPhone but the same methods can be used on iPads as well.

Press the volume up button of your iPhone and then immediately, release it.
Now quickly press the iPhone’s volume down button and immediately, release it.
Afterward, press and hold your iPhone’s side button.

Force Restart the iPhone
Then keep holding the side button till the screen shows the Apple logo (do not release the side button when the iPhone’s power menu is shown) and then release the side button.
Now, wait till your iPhone is properly powered on, and once done, check if you can update the iPhone to the latest iOS.

2. Create Space on Your iPhone and Re-download the Update

If your iPhone is running out of space, then that will cause the update issue under discussion as the update have no space to execute. Also, if the downloaded update is corrupt, then that will also cause the update issue. In this context, creating space on your iPhone, deleting the old downloaded update, and redownloading the update may clear the problem.

Go to your iPhone Settings and select General.

Open General Settings of iPhone
Now open iPhone Storage and make sure you have more than 10GB of space available. If not, uninstall some apps and delete non-essential data.

Open iPhone Storage in the General Settings of Your iPhone
Then delete the old downloaded update and to do so, select your iOS version in the iPhone’s Storage settings and tap on Delete Update.

Delete iOS Update in the iPhone Storage Settings
Now confirm to delete the iOS update and restart your iPhone.
Upon restart, check if the latest iOS update can be installed on your iPhone without any issue.

3. Disable the Low Power Mode of the iPhone

In the low power mode of the iPhone, only essential modules operate, and many of the background operations are halted. If your iPhone is in low power mode, then the installation of an iOS update will fail as the modules essential for the completion of the update are blocked from execution. In such a case, disabling the low power mode of the iPhone may solve the update problem.

Go to your iPhone’s Settings and select Battery.

Open Battery in iPhone Settings
Now locate Low Power Mode and disable it.

Disable Low Power Mode of the iPhone
Then restart your iPhone and upon restart, check if the iOS on your iPhone is updated to 15 or above.
If that fails, put your iPhone to the charge and wait till it is fully charged.
Once done, check if the phone’s iOS can be updated to the latest build.

4. Disable the VPN of the iPhone

If your iPhone is routing its traffic through a VPN, then that could result in the iOS update issue at hand as the Apple servers may refuse to verify the connection from a VPN as many people use a single IP. In this case, disabling the VPN of your iPhone may let you update the phone’s iOS to the latest build.

Go to Settings of your iPhone and open General.
Now select VPN or VPN & Device Management.

Disable VPN in the iPhone Settings
Then open VPN and on the VPN Configurations section, disable VPN by toggling its switch to the off position.
Now restart your iPhone and upon restart, check if your iPhone can be updated to its latest iOS.

5. Sign in to the Feedback App

If you are on the beta release channel of iOS for your iPhone, then you may fail to update the iOS to 15 or above if you have not signed into the feedback app as it is used by Apple to measure the performance of different OS modules in the beta environment and failing to do so, it will result in the issue at hand. In this context, signing into the feedback app may clear the error that occurred installing iOS 15 or above.

Launch the Feedback app from the Home screen on your iPhone and give it the required permissions (if asked to).

Sign in to the Feedback App on the iPhone
Now sign into the Feedback app and once done, restart your iPhone.
Upon restart, check if the iPhone can be updated to iOS 15 or above.

6. Disable Private Relay in the iCloud Settings

Apple has equipped its OS with a new privacy entity called Private Relay. This entity uses a novel dual-hop architecture i.e., this architecture separates the user’s IP address from the website he visited and no single organization holds this critical information combined.

If you have enabled this setting in the iCloud settings of your iPhone, then the relayed traffic between your device and Apple servers can corrupt essential update-modules during the transmission, thus an error occurred installing iOS 15 or above. In this scenario, disabling the Private Relay feature in the iCloud settings of your iPhone may clear the update issue.

Go to your iPhone Settings and tap on your ID.
Now open iCloud and select Private Relay.

Open iCloud Settings on iPhone
Then disable Private Relay by toggling its status switch to off and restart your iPhone.

Disable Private Relay in the iCloud Settings of Your iPhone
Upon restart, check if the iOS update issue is cleared.

7. Try Another Network or Network Type

If the network modules (like Wi-Fi and cellular) of your phone are glitched out or if the data packets exchanged between your device and Apple servers have become corrupt due to ISP’s hindrance, then that could result in the update error at hand. In this context, trying another network or network type may clear the iOS update issue.

Firstly, check if connecting the iPhone to the 2.4Ghz band of your Wi-Fi network (if available) clears the error.
If not, disconnect your iPhone from the current Wi-Fi network and connect it to another Wi-Fi network (not a hotspot from another phone).
Then check if the phone’s iOS can be updated to the latest build.
If the above did not work or no update was shown on your Wi-Fi, restart the iPhone and upon restart, download the update on the Wi-Fi but do not install it.
Now go to Settings of iPhone and disable Wi-Fi.
Then enable cellular and head to the update menu on your iPhone.

Disable Wi-Fi on the iPhone and Open Mobile Data
Now tap on install and once the update is verified, enable Wi-Fi.
Then procced with the update and afterward, check if the update installs fine.
If that did not work, restart your phone and upon restart, disable Wi-Fi.
Now enable cellular and check for updates.
Once the update is shown, enable Wi-Fi and proceed with the update to check if it has updated to iOS 15 or above.

8. Reset Network Settings of the iPhone to the Defaults

If the iPhone’s network settings are corrupt, then that may cause the iOS update issue at hand as some network settings can block access to the components essential for the update. In this case, resetting the network settings of your iPhone to the factory defaults may solve the iOS update problem. Before proceeding, make sure to note down the details (like Wi-Fi credentials) required to re-setup networks on your phone.

Launch the Settings menu of your iPhone and select General.
Now open Reset and afterward, tap on Reset Network Settings.

Open Reset in General Settings of Your iPhone
Then confirm to reset the iPhone’s network settings.

Tap on Reset Network Settings in iPhone
Once done, restart your iPhone and upon restart, check if the iOS update problem is cleared.
If not, delete the update from the iPhone (discussed earlier) and remove the SIM card from your iPhone.

Remove SIM Card from iPhone
Now check if the iPhone can be updated fine.
If not, check if reinserting the SIM card into the iPhone clears the update error

9. Remove the Passcode from the iPhone

There are some iDevices (like iPads, iPhones, etc.) that have reported issues when updating to iOS 15 or above if a passcode is enabled on the iPhone. In this context, removing the passcode from the iPhone may let you update your iPhone to the latest iOS.

Go to the iPhone Settings and open Touch ID & Passcode or Face ID & Passcode.

Open Touch ID & Passcode
Then enter your iPhone’s passcode and afterward, tap on Turn Passcode Off.

Turn Off Passcode on the iPhone
Now confirm to disable the iPhone’s passcode and then restart your iPhone.
Upon restart, check if the iOS on your iPhone can be updated successfully. If so, then you may enable back the passcode on your iPhone.

10. Delete Security Profiles on Your iPhone

If you have installed any type of security profiles on your iPhone like profiles from an ISP (e.g., Xfinity) to connect to the ISP’s hotspot, then that could result in an error occurring installing iOS 15 and above as these profiles may conflict with the requirements of the iOS update. In this scenario, deleting the security profiles on your iPhone and resetting network settings to the defaults may solve the update problem.

Go to the iPhone’s Settings and open General.
Now select Profile or Profiles and Device Management.

Delete Profiles on the iPhone
Afterward, remove any profiles shown. You may note down the details of the profiles as you may need them later on.
Then reset the network settings of your iPhone (discussed earlier) and connect the iPhone to a private Wi-Fi network (e.g., a network in your home), not to a public, corporate, or enterprise hotspot.
Now check if the iPhone is clear of the error that occurred while installing iOS 15 or above.

11. Update the iPhone to the Latest Version of iOS Through a PC

If none of the above worked for you, then you may update your iPhone to the latest version of iOS through a PC. For illustration, we will discuss the process through iTunes on a Windows PC. Before proceeding, make sure the iPhone is fully charged.

Firstly, make sure to back up the essential data on your iPhone and then delete the old downloaded file from the iPhone (discussed earlier).
Then launch the iTunes app on your Windows system and open Help.
Now select Check for Updates and if an iTunes update is available, download and install it by following the prompts on the screen.

Check for iTunes Updates
Once done, close iTunes and connect your iPhone to the PC. You may use a USB cable, USB-C cable, or wireless.
Now launch iTunes and select your iPhone (near the top left).

Check for Update for iPhone Through the iTunes
Then click Check for Updates and if an iOS update is available, download and install it.
Once installed, hopefully, it will be clear of the error that occurred installing iOS 15.
If an error occurs, check if removing the SIM card and retrying the above steps clears the error.
If not, remove the passcode on your iPhone (discussed earlier) and retry the above steps to check if that resolves the issue.

12. Reset Your iPhone to the Factory Defaults

If none of the above worked, then the corrupt OS of your iPhone could be the root cause of the update issue under discussion. In this case, resetting your iPhone to the factory defaults may let you update your iPhone to the latest iOS. Before proceeding, make sure to create a backup of your iPhone (preferably, on a system).

Launch the Settings of your iPhone and head to General.
Now open Reset and afterward, select Erase All Contents and Settings.

Erase All Content and Settings of iPhone
Then confirm to factory reset your iPhone by selecting Erase Everything and wait till your iPhone’s reset process finishes.
Once done, re-setup your iPhone (as a new one), and afterward, hopefully, you will be able to update it to iOS 15 or above.