Why is my iPhone 12 unable to install iOS 18.3.1?

I currently cannot install iOS 18.3.1 on my iPhone 12 64GB - I have been able to detect the software update, and then download it. However, when it comes to downloading it to the phone, it says 'error cannot download, try again'.


Confirmations about my phone because of prior suggestions:


  • My iPhone has a fast Wi-Fi connection.
  • I do not have a beta updates activated in Settings
  • The iPhone is not in Low Power mode
  • The battery state of charge is above 50%
  • My iPhone has more than 20GB freestorage space
  • My iPhone is not connected through VPN
  • I have left the phone on charge whilst trying to do the update


I have tried everything suggested by the Apple Community team so far - I am very welcome to hearing more ideas.


This is currently very frustrating as I have just bought an apple watch series 10 and cannot use it without this iOS.


Thank you for your feedback



[Re-Titled by Moderator]

iPhone 8 Plus, iOS 14

Posted on Feb 11, 2025 5:43 AM

Reply
Question marked as Top-ranking reply

Posted on Mar 5, 2025 5:28 PM

It sounds like just about the only thing that you haven't tried is installing iOS 18.3.1 with the help of a Mac or a PC.


If you have put off updating for a long time (especially if you're still on iOS 14.1 – iOS 16.7.10), your odds might be better with a computer-assisted update than with a wireless one.

13 replies

Feb 12, 2025 12:55 PM in response to SamRico

I'm experiencing a similar issue, where the software appears to be downloaded and then we get to an endless "Preparing Update" phase, at which point the software update appears to get stuck in a loop? This is a new iphone locked to straighttalk, it is also failing to activate imessage, which community recommends completing updates for. Seems that this update has to be cleared before I can address imessage activation.

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Why is my iPhone 12 unable to install iOS 18.3.1?

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