SE2 iOS update fails; 'Unable to Activate' after restart
SE2 would not update from iOS 26.1 to iOS 26.2. I Did a full restart and when trying to restart device I received a Unable to Activate message.
iPhone SE (2nd generation)
SE2 would not update from iOS 26.1 to iOS 26.2. I Did a full restart and when trying to restart device I received a Unable to Activate message.
iPhone SE (2nd generation)
Cellular Update Failed —> If you see an Update Failed or Apple Pay Not Available alert after iOS update or restart

Settings > Mobile Data > APN [under Mobile Data APN] enter the APN pin
View and edit your APN settings
If your carrier allows it, you can view your APN settings in one of the following locations: Settings > Cellular > Cellular Data Options > Cellular Network. Settings> Mobile Data > Mobile Data Options > Mobile Data Network.
View and edit your Access Point Name (APN) on your iPhone ...

Carrier Update (Required): Released by your Cellular Service provider (Carrier Update), affects your Outgoing / Incoming calls, SMS, Data etc..
How to Update Carrier Settings
You can manually check for and install carrier settings, and update with these steps: Make sure your device is connected to a Wi-Fi or cellular network. Tap Settings > General > About. If an update is available, you'll see an option to update your carrier settings.
Update your carrier settings on your iPhone or iPad - Apple Support

If nothing helps then --> If you see a Cellular, Ultra Wideband, or Apple Pay Issue message after an iOS update or restart

Reset Network Settings: Only network settings are removed.
If the above fails...

Reset All Settings: All settings—including network settings, the keyboard dictionary, the Home screen layout, location settings, privacy settings, and Apple Pay cards—are removed or reset to their defaults. No data or media are deleted.

If you see No Service or Searching on your iPhone or iPad
If you see No Service or Searching on your iPhone or iPad ...

Remove your SIM card from the SIM card tray and then put the SIM card back. ... Make sure that the SIM tray closes completely and isn't loose. If you use a SIM tray from a different model iPhone, iPad, or from another phone manufacturer, it might not fit properly.
If you see 'invalid SIM' or 'no SIM' on your iPhone or iPad ...

Learn what to do if you see a SIM not supported alert.

If you see No Service, Searching, or SOS on your iPhone or iPad
If you see No Service, Searching, or SOS on your iPhone or iPad

To be able to use any SIM across the globe you must have "No SIM Restriction" against Network Provider Lock. Please refer to the pic below.

Cellular Update Failed —> If you see an Update Failed or Apple Pay Not Available alert after iOS update or restart

Settings > Mobile Data > APN [under Mobile Data APN] enter the APN pin
View and edit your APN settings
If your carrier allows it, you can view your APN settings in one of the following locations: Settings > Cellular > Cellular Data Options > Cellular Network. Settings> Mobile Data > Mobile Data Options > Mobile Data Network.
View and edit your Access Point Name (APN) on your iPhone ...

Carrier Update (Required): Released by your Cellular Service provider (Carrier Update), affects your Outgoing / Incoming calls, SMS, Data etc..
How to Update Carrier Settings
You can manually check for and install carrier settings, and update with these steps: Make sure your device is connected to a Wi-Fi or cellular network. Tap Settings > General > About. If an update is available, you'll see an option to update your carrier settings.
Update your carrier settings on your iPhone or iPad - Apple Support

If nothing helps then --> If you see a Cellular, Ultra Wideband, or Apple Pay Issue message after an iOS update or restart

Reset Network Settings: Only network settings are removed.
If the above fails...

Reset All Settings: All settings—including network settings, the keyboard dictionary, the Home screen layout, location settings, privacy settings, and Apple Pay cards—are removed or reset to their defaults. No data or media are deleted.

If you see No Service or Searching on your iPhone or iPad
If you see No Service or Searching on your iPhone or iPad ...

Remove your SIM card from the SIM card tray and then put the SIM card back. ... Make sure that the SIM tray closes completely and isn't loose. If you use a SIM tray from a different model iPhone, iPad, or from another phone manufacturer, it might not fit properly.
If you see 'invalid SIM' or 'no SIM' on your iPhone or iPad ...

Learn what to do if you see a SIM not supported alert.

If you see No Service, Searching, or SOS on your iPhone or iPad
If you see No Service, Searching, or SOS on your iPhone or iPad

To be able to use any SIM across the globe you must have "No SIM Restriction" against Network Provider Lock. Please refer to the pic below.

“SE2 iOS update fails; 'Unable to Activate' after restart: SE2 would not update from iOS 26.1 to iOS 26.2. I Did a full restart and when trying to restart device I received an Unable to Activate message.“
———-
Troubleshoot "Unable to Activate":
A. Start Here: If you can't Activate your iPhone - Apple Support
As it Reads: "If your iPhone can't be activated or an alert says the activation server is unavailable or the SIM card is unsupported, learn what to do."
B. Install a Cellular Update:
Your device is quite old. So, that may be the culprit. But, before making that assertion, try the following. It might be prompting you for a cellular update to install. So, go here for that. Update your carrier settings manually on your iPhone or iPad - Apple Suppor
LineChief wrote:
I received a Unable to Activate message.
To activate iMessage and FaceTime using your Phone number
*** You may not have an SMS plan (Domestic & International) enabled by your carrier for the SIM/eSIM that you use on your device. Apple Inc. does not provide SMS services.


SE2 iOS update fails; 'Unable to Activate' after restart