iOS 15.6 not updating, won't install

If updating wirelessly isn't working, please try and update via a pc or mac

Update your iPhone using a Mac with macOS Catalina or higher

On a Mac with macOS Catalina or higher, you will use the finder in order to upgrade your iPhone. Make sure to Back up your device before starting the upgrade process.

On a Mac with macOS Catalina or later, you will follow the following steps:

1. Open a finder window
2. Connect your device to your Mac via a lighting to usb A or a lightning to usb c cable
3. Select your device in the left sidebar of the finder window
4. click general, then click check for update
5. Click download and update.
6. If asked, enter your iPhone passcode

Update your iPhone via a Mac running macOS Mojave or earlier, or on a Windows PC

On macOS Mojave or earlier, or on a windows machine, we won't use the Finder to upgrade your iOS

Instead, we will use iTunes. Make sure to Back up your device before doing any update or upgrade to your phone.

1. Open iTunes
2. connect your device to the computer with an lightning to usb a or a lightning to usb c cable
3. Click device button in the iTunes toolbar
4. In the summary tab, click check for update
5. Click download and update, follow The on screen instructions
6. If asked, enter your iPhone passcode.

We assume that you really do have a good Internet connection and the VPN....if you have one installed.....is turned off.

Check to make sure that you don't have a previous update that was not installed, or not installed correctly.

1. Go to Settings > General > [Device name] Storage.
2. Find the update in the list of apps.
3. Tap the update, then tap Delete Update.
4. Go to Settings > General > Software Update and download the latest update again

If still no luck, we'll have to try updating using a Mac or PC

Do this

Check to make sure that you don't have a previous update that was not installed, or not installed correctly.

1. Go to Settings > General > [Device name] Storage.
2. Find the update in the list of apps.
3. Tap the update, then tap Delete Update.

4.***Restart your phone powering off then back on

5.Go to Settings > General > Software Update and download the latest update again

I have had the exact same problem. Same message etc.

Mine just says "Unable to Install Update. An error occurred installing iOS 15.6. Retry" I've retried several times. I will connect my iPhone to my MacBook and keeping fingers crossed.

My sister got the same message on her iPhone 7. I had her check her storage and she was almost full. Created about 6 GB of free space and the update went through.