Unable to install iOS 16.3 on 2023-01-26 - retry or try again later

To update over the air from the phone all of these requirements must be met:

• You need at least 10 GB of free storage for iOS 16 or 6 GB for iOS 15 or lower; more is better
• You must be connected to a Wi-Fi network (and not a personal hotspot)
• The phone must be charged to at least 50%, and preferably plugged in so it stays above 50% during the update
• The phone must not be in Low Power Mode
• The phone must not be connected through VPN, and it may be necessary to delete any VPN apps and VPN profiles
• The phone cannot be in Airplane mode and must have a cellular data connection
• You cannot still have a beta version installed on the phone
• You cannot have a previous version that was downloaded, but not installed - go to Settings/General/iPhone Storage to look; if you find an iOS installer, delete it

If you can't meet all of them you can still update using your computer.

My problem with installing IOS 16.3 was that my iPhone 11Pro didn't have enough memory available. Mine would not even download. I had to delete some Apps and then it downloaded and installed. The installation took a while as did the download and I have a fast Internet.

The installation program is supposed to automatically remove apps and then reinstall them after the installation is complete. This didn't work for me. It does take while to download and a while to install.

Mine seems to be working just fine, but I haven't tried everything new yet..

It's unlikely you would be the only one out of millions.

Perhaps this will help. If your iPhone or iPad won't update - Apple Support