Step one, back up data
1
Before you start, if you have already backed up the data before upgrading to iOS 9, or there is no important data on your phone, you do not need to back it up again. But if there is some important information on your phone, such as contacts, text messages, photos, etc., and it has not been backed up, it is recommended to back it up first.
2
It is usually recommended to use the iTunes software on your computer for backup, because it can provide a more comprehensive backup function and will also be used when flashing. If iTunes is not installed on your computer, please go to Apple’s official website to download and install it.
end
Second step, return to ios8 system
We need to go online to download the latest iOS 8 version. The latest version is iOS 8.3. Downloads of iOS firmware can be found on many websites, take Weifeng.com as an example. At the same time, you need to make sure to download the version corresponding to your iPhone, otherwise it will not work.
After the firmware is ready, you can start downgrading to ios9. First, please connect your iPhone to the computer and open the iTunes software.
Then please press and hold the power button of the iPhone. After the shutdown option appears, please slide to shut down.
Then please follow the steps below to put the phone into recovery mode: 1. First, press and hold the power button to turn on the phone. The Apple logo will appear on the screen. Do not release the power button; 2. Then press and hold the home screen. key until the screen goes black. 2. When the screen is black, please release the power button and do not release the home button until itunes on the computer appears and detects an iPhone in recovery mode. For those who are operating it for the first time, they may not be familiar with it. Please try a few more times. times.
Next, please click the "Restore iPhone" button in the window, as shown in the figure below
Then please select the ios8 firmware we downloaded before. Note that the firmware here must end with ipsw.
We will then be prompted whether we want to continue doing this, and if we continue, all previous data on the iPhone will be cleared. Click the "Restore and Update" button to continue.
Please wait patiently for iTunes to extract the firmware and restore the ios8 system to the iPhone. After the downgrade is successful, we can activate our mobile phone.
I want to downgrade my ipad2 after upgrading. The specific tutorial is as follows:
1. After manual downgrading of ipad2, the original data will be lost, so you need to back up the photos, music and other data in your ipad first.
2. Search and download a firmware version you want to upgrade on your computer (not a tablet). For example, if you want to downgrade to a 7.12 system, download 7.12. When downloading, remember to select your corresponding tablet model to download.
3. Download the latest version of itunes on your computer, connect your ipad2, click the ipad icon in the upper right corner of itunes, hold down the shift key on the keyboard, and then click check for updates. In the pop-up firmware system file selection window, select the firmware version you downloaded locally on your computer and click Open.
4. Next, iTunes will pop up a page prompting that all content will be erased and the recovery will be verified with Apple servers. Click the Update button. When the verification and file extraction are completed, iTunes will automatically reinstall the iPad2 system.
1. Before flashing your phone, first make sure you have SHSH 4.3.3;
To downgrade to 4.33, you cannot downgrade unless you have a SHSH backup of 4.33. Now Apple has turned off the SHSH backup of 4.33. If you have not backed up the SHSH of 4.33 before, you cannot back it up now. If your iPad was installed with the 4.33 system and jailbroken, Cydia will automatically back up the 4.33 SHSH for you, and it is possible to obtain the SHSH through the small umbrella.
Generally, CYDIA who has jailbroken before will know that SHSH is saved on the server, so how do you know if you have it?
The best way is to use a small umbrella
Download tinyumbrella-5.00.06, (java must be installed to open the small umbrella)
Open the small umbrella backup, click the advanced page and check Request SHSH from Cydia
Select the device, click save shsh, and read the SHSH file that Cydia has backed up for you
After waiting for a while, a shsh document will appear in C:\Users\Administrator, which will contain your shsh file
Another thing you can try is:
If you want to confirm whether it is backed up in Cydia, please open Cydia while connected to the Internet
See the top row of green words: This device has SHSHs on file for iPhone OS: 3.1.3,
Indicates that Cydia has backed up shsh of 3.1.3. The same goes for other versions.
2. Restore firmware
First download the version of firmware you need to restore, and fixrecovery4.3
The process is:
1. Open the small umbrella, click start TSS sever, and then leave it alone, spinning in a circle;
2. Manually or with the help of Hongxue RC19 or iREB, put the phone into DFU mode;
(First press and hold the POWER button for 3 seconds
Press and hold the POWER HOME button for 10 seconds
Release the POWER button and press the HOME button for 15 seconds
The DFU mode at this time is a black screen. You have to rely on the sound of the connected computer to determine whether it has entered the DFU mode)
3. Open itunes, hold shift, click OK, then click restore, and then choose the firmware to flash. For the unlocked version, choose the 4.3.3 official firmware, and for the locked version, choose the 4.3.3 homemade firmware. Flash;
4. When error 1013 is reported, don't panic, and don't click OK in the error window. At this time, open fixrecovery4.3 in the attachment of the post. If you are prompted "No iTunesHelper", you can find the installation directory of itunes, and then Manually open iTunesHelper and run fixrecovery4.3 again. At this time, you will be prompted to "Waiting for device to enter DFU mode". You can manually enter the phone into DFU mode again. The next step is to wait. English will appear on both the phone and the computer. , the phone will restart after a few minutes, and the familiar activation interface will be connected to itunes. After doing this, there will be no bugs. (If an error occurs in fixrecovery4.3, please do not press OK or close the dialog box until the restart is successful)
After the activation interface appears, you can first unplug the connection cable and close the small umbrella and ITUNES. Reconnect the computer and open iTunes to reactivate.
Question
What should I do if I don’t have SHSH backup? ? ?
answer
If not, there is nothing we can do
Or just do an imperfect jailbreak of 4.3.5
Or just wait for the perfect jailbreak of 4.3.5 to appear
If you upgrade to the official version of iOS 8.2 just to try it out, if you want to downgrade, you can only choose to downgrade to the iOS 8.1.3 firmware version again. However, this method will not be effective for a long time. Generally, Apple will turn off the verification of the old system within a few days after the new system is released. At that time, you will not be able to downgrade through this tutorial.
Method 1: Official recovery
Downgrade instructions:
This method is suitable for operation when iOS8.1.3 system verification is not closed. [Check whether the relevant iOS8.2 firmware is turned off] If the verification is turned off, you cannot downgrade.
At that time, the iOS8.2 column showed a small green check, which meant that it could be downgraded to iOS8.2
Steps:
1. Connect your iPhone \ ipad \ iTouch and other devices to your computer and open iTunes.
Method 2: DFU mode recovery
Downgrade instructions:
This downgrade method requires entering DFU mode or recovery mode, which will erase all data on your device, so you need to back up your device in advance.
Steps:
1. After the iPhone is turned off, press and hold the Home button for 8 seconds, connect it to the computer through a USB data cable, or please connect the device to the computer, first press and hold the power button for 3 seconds, and then continue to press the power button and the Home button at the same time. At the 10th second, please release the power button immediately and continue to hold down the Home button until you see the USB device in the DFU state recognized on the computer and enter the DFU mode. At this time, iTunes will automatically or manually start up.
2. iTunes will automatically detect a device waiting to be restored, click OK.
3. Press and hold the shift key on the keyboard and click "Restore" on iTunes and select iOS8.2 firmware download
4. The device will begin to re-flash and restore to a brand new system.
10
5. After the recovery is complete, click "Set up as new device" on iTunes.
11
Follow the above two methods, you can downgrade the iOS device in your hand to iOS8.2.
The above is the detailed content of How to downgrade iPad 2 from iOS 9 to iOS 8. For more information, please follow other related articles on the PHP Chinese website!
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