iTunes won't restore iPhone from Backup. ("Backup Corrupted")

I got this on my iPad Air with 9b3 - nothing worked apart from setting up as a new iPad. My iPhone 6Plus was unaffected. This time round it's my iPhone that's got the problem 😟. I did an OTA with the iPad and it's fine.

I'm going to restore the iphone back to 8.4 then reapply 9b4 and see if I can restore the back up from 9b3 to it. Failing that it's the pain of setting it up from scratch.

UPDATE: Instead of going back to 8.4 I restored back to 9b3 and then restored the iTunes back up I took before trying to update to 9b4. It worked, so the backup can be restored to a phone running 9b3 but not 9b4. Next I'm going to do an OTA on the phone to get to 9b4.

Same issue here.

same process, however not OTA proposed, while I am a dev with registered device (OTA was also not working for beta 2 to beta3)

ok,here is the solution

restore your device back to iOS 9 beta 3 ( it is possible ) and restore all your backup. then go to Settings>General>Software Update. from there you can update to beta 4. you dont need to connect to computer anymore.

if you having problem to restore your backup on beta 3 do things from link below

https://forums.developer.apple.com/thread/8678

Ahmadreza

Where can I re-download the beta 3 file for my iPhone 6? It would appear they've taken them down by now and I've deleted it off my computer since its an extra 2GB of space!

Alex

Same here - where can we find the Beta 3 download as it has been removed? Have also tried the removal of the Homekit dir workaround but this has not worked at all yet so seemingly to go back to beta 3 is the only option.

Luckily, I had forgotten to delete my download of beta 3. I read your post, set up my phone as a new phone then restored to beta 3 then set it up using the backup that beta 4 kept saying was corrupt. As soon as that was finished, Software Update finally said I had an update OTA. I installed that without any issues (other than the way it kept/keeps using celluar data when connected to wifi).

Thanks for the tip.