According to Apple's past practice, after Apple launches a new version of iOS system, the system authentication of the old version of iOS will be closed! The closed system verification version means that as long as you upgrade the new version of iOS, you can no longer flash back to the old version of iOS. You can only use your latest version. As everyone said, all kinds of problems after the update can only be endured silently.

In this case, Apple said: "For security reasons, Apple does not allow the device to be downgraded because there is no latest security update."

At present, Apple has turned off the system verification of iOS 10.3.3 and iOS 11.0, which means that iPhone, iPad and iPod Touch users who have upgraded to iOS 11 will not be able to return to the previous system by swiping the machine!

It is worth noting that, However, Apple suddenly opened iOS 10.3.3 system verification again today, but only iPhone 6S can do it. Users who think iOS 11 is not good can try to reset to iOS 10.3.3.