There is no way of making the iOS 9 backup available to your phone running 8.4 through iTunes.You can recover lost iPhone data after iOS 9 upgrade
There is 3rd party software that can extract contacts, photos, etc. from a backup and then add them back to your iPhone. The two that come to mind are iMazing and iExplorer. Trial before you buy because there is no guarantee that slight changes made to the way iTunes backs up in iOS 9, hasn't broken the functionality for one or both of them.
|recover iphone data after ios 9 downgrade|
Method-1: Place your iOS device in DFU mode
For this, connect your phone to the PC
Switch off the device by holding Power button and do a swipe to turn it off
Hold the Power button again for about three seconds
Press the Home button while holding the Power button for about 10 seconds
Release the Power button while keep holding the Home button until a pop up from iTunes appears that reads it has detected your iOS device which is in Recovery mode
Click OK then click Restore iPhone or iPad or iPod touch whatever you have
Click the Restore and Update button to proceed further
On the next screen you should find information about iOS update, click on Next then Agree to continue
iTunes will now start downloading and installing iOS 8.4.1 update on your device. This process will take about 10 minutes
When iOS 8.4.1 is successfully installed, follow the on-screen instructions to set up your device and restore your personal data
Method-2:Disable Find my iPhone feature from Settings>> iCloud
Download iOS 8.4.1 firmware according to your device's model number
Connect your iPhone/iPad to the PC
Launch iTunes and select the iS device
Hold Alt/Option key on Mac, or Shift key on Windows and click Check for Update option, but not Restore iPhone option
Select the ipsw file you have downloaded in previous step
iTunes will now update your device to iOS 8.4.1 and verify it with Apple. Click Update
iTunes will downgrade your iOS device to iOS 8.4.1
Once the process is completed, your iOS device will restart. Once you see Slide to upgrade, enter your passcode and wait until the downgrade process finishes. You might get prompt to activate your device
Your iOS device will now be ready to get started with the older iOS 8.4.1 firmware.
Once lost data on your iPhone after downgrade from iOS 9 to 8.4,you can recover iPhone iPad data after downgrade from iOS 9 to 8.4 without losing data.All you need is a professional iOS 9 Data Recovery software.
The iOS 9 iPhone Data Recovery not only can help you recover lost data from iPhone iPad after upgrading to iOS 9/iOS 8,but also allows you restore iPhone lost data when failed iOS 9 update,and get back lost data after downgrade from iOS 9 to 8.4.You can use this iOS Data Recovery for Mac to restore your lost files after upgrading your iPad,iPhone to iOS 8 or iOS 9 by extracting the iTunes backup on Mac. In addition, the data recovery software can help you to recover lost contacts, text messages, photos, videos, notes,ect from iPhone, iPad directly.
Read more: Recover Data from iPhone After iOS 9 Upgrade Failing
Part 1: Restore iPhone Lost Data After Downgrade from iOS 9 to 8.4 Directly
Step 1 Connect iPhone and Scan the phone
With the saind program running on yor PC, connect your iPhone iPad or iPod with USB cable. When you see the homepage as below, click on Start Scan.
You may check the box infront of Contacts from the left list. In fact, you can check any box you like if you need to get them back.
Your wanted contents will be listed in categories after the above steps. You can overview the scanning result and click Recover to extact them.
If you can not find your data by using the method that shows in Part 1, you can also try using the below two ways to extract lost iPhone data from backups.
Part 2. Extract Disappeared Data from iTunes Backup
Step 1 Scan lost data from iTunes Backup
On the hompage, click on "Recover from iTunes Backup File". You can choose the backup file according to the backup date. Then click "Star Scan".
Step 2 Overview your Phone Data
It will not be long before the scan process finishes. After that, select the content you want and click "Recover" button to get back your contacts, SMS or any others.
Part 3. Extract Disappeared Data from iCloud Backup
Step 1 Sign in to iCloud
Start iOS Data Recovery Program and choose "Recover from iCloud Backup File" mode. You need to sign in your iCloud.
Step 2 Download iCloud backup
Download the imformation you need, and move on to the next step.
Step 3 Get Whatever Wanted Lost Data Back
This step is more of the same as recovering data from iTunes Backup File. That is, choose contents you like, and finally, click "Recover".
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