Attention! In the article, I use screenshots from the iPod Touch, but this does not play a significant role. These instructions are equally relevant for the iPad, iPhone or iPod Touch.
Rollback iOS firmware (Downgrade iOS) – installation of an older version of the firmware. Previously, rolling back firmware to older systems, although difficult, was more likely. To do this, the user had to save SHSH certificates (digital signature unique to each device).
In this case, we roll back iOS 9 to iOS 8. These two systems support: iPad 2, iPad Mini 1, iPhone 4s, iPod Touch 5G and newer devices in the line. For all these devices, rollback is possible. exclusively on iOS 8.4 (as of July 12, 2015) even with the SHSH saved.
Now the general case. As a rule, rollback to an older firmware version is possible:
a) if the previous firmware is still considered relevant. For example, the whole world is currently testing iOS 9 Public Beta. The official version of iOS 9 will be released in the fall. So, up to this point, the user has the opportunity to flash his device to the official official iOS 8.4.
b) if a new official firmware has just been released. For example, after the official release of iOS 9, the user will have from 1 to 7 days (maybe a little more) to change their mind and roll back. At some point, Apple suddenly ceases to sign old firmware, and then rollback is impossible or substantially difficult.
The rollback instruction in this case is identical to the firmware through recovery
Step 1. Download the firmware from your device, which you can roll back to.
Step 2 Disable the function: “Find iPad, iPhone or iPod” (depending on your device). Settings->iCloud
If this is not done, then iTunes will not allow you to carry out the firmware. After flashing, do not forget to enable the option back.
Step 2 We connect the device to the computer through the cord. We go into iTunes and select the device. We are looking for the “Restore” button and press with the pre-pressed Alt-Option key (in OS X) or Shift (in Windows).
In the new window, select the downloaded firmware. Then in the window that appears, click “Restore” and the recovery / rollback process begins.
This must be remembered!
The device will revert to the factory settings. That is, before starting the system you will have to reconfigure it (you must at least know the password from the Wi-Fi network).
A backup copy to an older firmware can only be rolled up if you still have a backup copy made on the old firmware. Including, therefore, it is recommended that you save a backup copy to your computer before iOS firmware.
All a successful rollback! 🙂 If you have any questions, additions or problems – write.