I downloaded 16.3.1 but I can’t install it on my iPhone.

The latest version of iOS is 16.7.1, where are you trying to install 16.3 from?

Go to Settings > General > Software Update.

This link will show you how to update your iPhone, iPad, or iPod touch using WiFi -

Update your iPhone or iPad - Apple Support

This link will show you how to update using your computer -

Update iOS on iPhone - Apple Support

If your phone won't update -

Can you post a screenshot of the whole screen, it could reveal why you aren't able to update.

Make sure you:

• Are using a WiFi connection (not a hotspot).

• You have an active cell signal (You need both WiFi and cellular service to perform the upgrade).

• Are not using a VPN connection.

• Have your battery charged at least 50%. Better yet, keep it plugged in during the update.

• Do not have power save mode turned on.

• Do not have a beta version installed.

• You have at least 10 gigs of storage available.

Click on this link on what to do if you can't update your phone -

If your iPhone or iPad won't update – Apple Support (UK)

So I think I found a fix. Go to Settings>General>Software Update>Automatic Updates. Turn off Automatic Updates restart your phone. Then go back to the update and see if you can request it manually. It took a little while and restarting the phone once or twice more, but it finally let me download and install the update. Hopefully it works for others, since clearly Apple doesn’t have a solution.

1. Manually delete the update: Settings > General > iPhone Storage
2. Search for ios 16.3.1
3. Delete it
4. Go back to Settings > General > Software Update
5. Try again dowloading and installing the update

Hi Hassanmidawa,

We'd love to see if we can help out. We don't see a clear issue here, as it can take some time for the installation to start. Are you getting an error message? If not, we recommend try to restart your device, then trying again to see if that resolves the issue. This will help if something in the process is stuck. If that does not help, please follow the steps below to continue troubleshooting the issue until it is resolved.

• Check to make sure you have enough available storage.

"If there isn't enough space to download and install an update, the software on your device will try to make space. It will remove only app data that it can download again and doesn't remove or relocate any of your data. If your device still doesn't have enough space, you can use your computer to update your device.

If you can't connect your device to your computer, you can make room for the update by removing content and apps on your device that you don't use. Go to Settings > General > [Device name] Storage.

Learn more about the space your apps and content use.

• If the update doesn't complete

If you're installing the update, the progress bar might appear to move slowly. The time an update takes depends on the size of the update and the number of files on your device.

When you're updating over the air, keep your device connected to a power source. If your device runs out of power, connect it to a power source and turn on the device to let the update or restore complete.

Learn what to do if your iPhone or iPad appears frozen or won't start.

• Remove and download the update again

If you still can't install the latest version of iOS or iPadOS, try downloading the update again:

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."

Reference: If your iPhone or iPad won't update - Apple Support

Cheers!

I had the same issue on my XR, the update downloaded but failed to install. I followed the steps below.

> Turn off Wifi and Mobile data- Restart the phone - Disconnect/reconnect wifi - settings - software update - download and install. It worked.

Mine did this after I turned off automatic updates. I restarted again a day or two after I got the “update requested” message that wouldn’t go away and it finally let me manually download the update. Maybe try another restart if you haven’t yet. Not sure it really helps, but it seemed to for me.

for info, after battling for weeks with 16.3.1 and never succeeding in downloading it, I recently updated to 16.4 with no issues at all

I’m having the same issue. iPhone 14 Pro. Just bought 2 months ago. I keep getting an error message when trying to install that says “Unable to install”. See below. I have plenty of storage, so I don’t think it’s that.

Same here. iPhone 11. Allowed me to download the update but won’t install. Plenty of storage space for it.

I'm getting the same error message. Iphone 12 pro. Plenty of space, connected to wifi, no other obvious issues. Stuck in a "cannot install" error loop whenever I try to install it.

Is Apple going to respond to these issues?

I used the method suggested by @joncooke above and it worked, but it did take a couple of restarts including just shutting down on its own. When it finally came back up the update had been installed. Thanks @Joncooke!

I have a 13 pro...install isn't my issue because I can't download it... I just keep getting the Software Update Failed message....my phone is nagging me to do the 16.3.1 update but I can't advance beyond Software Update Failed!!!!

Same issue

I’m having exactly the same issue as described in this thread. iPhone, 14 promax

Same issue. 11 Pro max