Unable to Install iOS 15 Update An Error Occurred on iPhone, iPad: here’s Fix

Last Updated on Sep 21, 2021

We tested on Thousands of iOS devices and found a solution that helps to fix the Unable to install iOS 15 Update & An Error Occurred Installing iOS 15 on iPhone/ iPad/ iPod Touch popup on the screen. At the last moment are you getting unknown reasons with your device only but your Friends or Family device installed iOS 15 Successfully? So this is not fair to you, But some internal software issues and Pre-defined solutions that apple doesn’t show the exact reason on the iOS device screen when this happens.

we are happy to help you, submit this Form, if your solution is not covered in this article.

As of now, there are more than 15 iOS updates have been released and none of them were bug-free. But iPhone users have a blessing that they can fix the toughest problems occurring on their own. While few users are happily enjoying iOS 15 on iPhone and some are unable to download iOS 15 on iPhone.

The downside is, we don’t know the cause of being unable to update the iPhone, but we know how to deal with it. With our mentioned workarounds your iPhone will be able to install iOS 15. Head over to learn, below are the key point that we should follow the try to fix own self without wasting time and money.

iOS 15 comes with the latest Security fixes and Fixes an issue where iPhone models with Touch ID cannot unlock a paired Apple Watch using the Unlock with iPhone feature.

Troubleshooting Steps for Unable to Install iOS 15 & An Error Occurred on iPhone

Solution 1: Check the iPhone Storage Right Now

New iOS install installation required free Gigabytes of Storage on iOS device, Sometimes small software updates in a whole year required Small space usually. So first check the New Software Update Size and Prepare your device by free up space. If your iPhone is failing to install iOS 15, then, first of all, you should verify there is enough storage to download the update. Continuously storing videos and images can lead you to insufficient space. Try to remove the files that you don’t require. Here’s how to check the storage on the iPhone, I recommend deleting Video files or move to another device or Mac/PC. Normal length video contains 1 or 2 Gbs space.

Check Updated Storage Space: Go to the Settings app > General > About > Scroll and Find Available space in GB.

Quick Way to Free Up Space: Go to the Settings app on iOS device > General > iPad/iPhone Storage > Here are the recommendations like iCloud Photo enable, Empty Recently Deleted Album. and Next is the Photos option, Click on it and the last option is Review Personal Videos. Here we can play video and Delete according to need and Storage required. Delete Video, Swipe To left, and tap on delete. Move back and don’t miss to empty Recently deleted album. Check my Video Tutorial to get easy understand,

Try Installation again,

  • Step #1: Go to the “Settings” app.
  • Step #2: Tap “General”.
  • Step #3: Tap “Software Update”.

From here you will get the actual idea of how much storage do you need to install iOS 15 on the iPhone.
Now, make sure that your iPhone has adequate storage to install iOS 15.

Solution 2: Reset Network Settings

Reset Network Settings not only forgot the connected or paired device but also reboot the device that built the WiFi system file on your iOS device. This is an easy and common practice to fix Network related issues on iPhone/iPad/iPod touch.

  • Go to the Settings app > General > Reset > Reset Network Settings.

Solution 3: Make sure WiFi is connected after Reset Network Settings

After Reset Network settings, All Saved WiFi passwords will be erased, Now Rescan your Home/Office network and connect to your iPhone/iPad. I hope you know that updating the iPhone requires an efficient internet connection or else there are more chances of receiving such errors. To make sure your Wi-Fi is perfectly working, try to use YouTube. Alternatively, connect your iPhone with your friend’s or colleagues’ Wi-Fi and try to luck by downloading iOS.

Step #1: Unplug the Wi-Fi router and plug it back in after 10 minutes.
Step #2: If it doesn’t work then you need to urgently contact the service provider.

Solution 4: Delete and Re-Download the iOS 15 Update file

This error message came on screen after the new iOS setup file is downloaded but was unable to start the installation. That means the problem with the Corrupted iOS file or incompatible version. I recommended to Delete downloaded iOS files from the device and re-download on iPhone/iPad/iPod Touch from the settings app.

Go to the Settings app > General > iPhone Storage and Scroll down and find file name with iOS 15 Swipe left and delete it.

When I was installing iOS 15 Beta updates in my iPhone 12 Pro Max, the systems say they were unable to install the update an error occurred installing iOS 15 Developer Beta. But then I tried a few troubleshoots and my problem gets resolved by just re-downloading the update file. In some cases, our iPhone ends with a corrupt iOS 15 Update file and so it happens. Go to the Settings  > General > Software Update > Download and install New software.

Solution 5: Force/Hard Reboot iPhone [Important]

Better late than never, we recommend you to force restart your iPhone and again try to update your iPhone. Occasionally simple restarting fixes many vigorous problems.

For iPhone 8/X/XR/XS Max or later: [No Home button iPad users can use below steps]
Step #1: Press and quickly release the Volume Up button.
Step #2: Press and quickly release the Volume Down button.
Step #3: Press and hold the Side button until the Apple logo appears on the screen. Use the Side button only to turn on the iPhone.

For iPhone 7/7 Plus:
Step #1: Press and hold Volume Down and Power button until you see the Apple logo on the screen.

For iPhone 6S Plus or earlier: : [Home button iPad]
Step #1: Press and hold the sleep/wake button and Home button and release them when you see the Apple logo on the screen.

Solution 6: Download iOS 15 using iTunes/Finder on Mac

Still, you are unable to install iOS 15 on iPhone? Then I have a way through which you might get iOS 15 on your iPhone. In this trick, I will show you how to install iOS 15 on iPhone using iTunes. Or you can say it is the best alternative way to install iOS 15 on iPhone.

Step #1: Connect iPhone to Mac/PC using the Lightning cable. Unlock the device and Enter the passcode to access your iPhone to Mac or PC.
Step #2: Launch “iTunes”. Make sure iTunes is updated. or Finder on Mac install macOS Catalina or macOS Monterey later [Apple Stopped iTunes officially]
Step #3: Select your iPhone. [On finder find it under the Locations section on finder sidebar,] Now you see the Device summary on Finder.
Step #4: Next, click on “Check for Updates”.
Step #5: Lastly, click “Download and Update”.
Step #6: Now, you have to follow the on-screen prompts.

Above all are working solutions for the problem of Unable to install Update – An Error Occurred Installing iOS 15 on iPhone/ iPad/ iPod Touch.

jaysukh patel

Jaysukh Patel is the founder of howtoisolve. Also self Professional Developer, Techno lover mainly for iPhone, iPad, iPod Touch and iOS, Jaysukh is one of responsible person in his family. Contact On: [email protected] [OR] [email protected]

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