iPad and iPod touch suddenly require activation I was using my iPad 2 today and everything was behaving normally. It had 90% battery and is running iOS 6.0. Then, suddenly, it displayed the Apple logo boot screen for a couple seconds and brought me to the device activation screen.

Upon my attempting to activate it, it tells me that "the activation server is temporarily unavailable" and suggests activating it with iTunes and a USB cable. When I proceed in this manner, iTunes shows it as a normal, activated device but refuses to sync with it.

A few minutes later, the exact same problem (and associated symptoms) occurred on my iPod touch (4th generation), also running iOS 6.

Additional info:


iTunes displays an alert, "The software on the [iPod/iPad] "[device name]" has expired and must be updated to a newer version." They are both completely up to date.
The contents of the devices are displayed perfectly fine in iTunes.
Both devices remember their lock screen backgrounds.
Syncing the device proceeds to step 5, until it says, "iTunes cannot sync apps to the [iPod/iPad] "[device name]" because the apps installed on the [iPod/iPad] could not be determined."


What in the world is happening, and how can I fix it?
This problem happened as the iOS 6 beta 4 expired today, so all devices that were running that version of iOS will need to be updated to the non-beta version. As iTunes and iOS don't see a difference between the two (as they're both called simply "6.0"), this update needs to be done manually, with the following steps:


Download the appropriate version of iOS 6.0 from the iOS Dev Center.
Connect the device to iTunes.
Option-click (Shift-click on Windows) the "Check for Updates" button on the Summary tab of the device in iTunes.
Select the .ipsw file in Finder and choose Open.


Your device will then install the update and everything should be fine.