Many iPhone 6/7/8 and iPhone X on iOS 11 users are facing issue while restoring their iPhone using iTunes and the iTunes error says “iTunes could not backup the iPhone because an error occurred while reading from or writing to the iPhone”. The iTunes restore error is with both windows and mac and fails to take backup.
The Apple has no official statement about why iTunes could not backup the iPhone and giving read write error. But there are some workaround available that you may try to fix the issue and take backup of iPhone using iTunes.
Fix 1: Authorize the PC for Apple id
In iTunes -> Look at the top menu. You'll see "Account", then Authorize, Select Authorize this computer. And this should fix any authorization related issue.
Fix 2: Remove old unsupported apps
Make sure to check all apps installed before iOS 11 and every apps open properly. In case you error while opening apps that saying the “developer needed to update them to work on ios11”. Please make sure to delete such apps from iPhone as they may not be supported on iOS11 and creating issue while restore or backing up iPhone.
Fix 3 : iPhone passcode and autolock
The error may occur while trying to take iTunes backup from encrypted backup and workaround to fix this issue is to remove iPhone security settings. First Disable Auto Lock, Disable Passcode and now start restoring the device from backup while making sure device is unlocked.
Fix 4: Make sure sufficient storage in iPhone and PC
You should have almost double the space of your backup file to be able to restore in your PC. So if you have 10 GB iPhone data size, make sure you have at least 20 GB space available in your PC.
Workaround: Take iCloud backup rather than iTunes
You may also try to take backup over iCloud rather than from PC and iTunes. Go to iCloud make sure iCloud back up is on Then backup now over your wifi. You should not face iPhone backup issue anymore.