How to Restore an iPhone without upgrading the iOS?

[Hoff]

I want to restore my iPhone 6 from a backup on my iTunes.
But I don't want to update the iOS because it will slow the phone down to unusable speeds.
It's currently on iOS 10.0.1 which runs pretty well.

How would I restore it without updating the iOS?
Has anybody done that before?

 

[Apple_Robert]

I may be wrong but, I don’t believe it is possible. Apple is no longer signing iOS 10.01 as far as I am aware.

 

[BugeyeSTI]

I want to restore my iPhone 6 from a backup on my iTunes.
But I don't want to update the iOS because it will slow the phone down to unusable speeds.
It's currently on iOS 10.0.1 which runs pretty well.

How would I restore it without updating the iOS?
Has anybody done that before?

You can try: settings/general/reset/erase all contents and settings. Not sure if it will work but I can guarantee if you try and restore using iTunes or any existing backup it will force you to upgrade to 12.4.8. All other versions of iOS for your phone are no longer signed by Apple.

 

[Hoff]

I don't know what it means that the iOS is not signed by Apple.
I have a back up which should include the iOS 10.0.1 so hopefully that's all I would need.

I don't see why they wouldn't let us reformat our phones with the same iOS on them.
Reformatting and upgrading are (or should be) two different things.

 

[C DM]

I don't know what it means that the iOS is not signed by Apple.
I have a back up which should include the iOS 10.0.1 so hopefully that's all I would need.

I don't see why they wouldn't let us reformat our phones with the same iOS on them.
Reformatting and upgrading are (or should be) two different things.

Backups do not include the OS itself, just your data basically.

 

[BugeyeSTI]

I don't know what it means that the iOS is not signed by Apple.
I have a back up which should include the iOS 10.0.1 so hopefully that's all I would need.

I don't see why they wouldn't let us reformat our phones with the same iOS on them.
Reformatting and upgrading are (or should be) two different things.

As @C DM stated your backup doesn't have a copy of the OS. It will ask Apple servers for the OS and when it sees it isn't allowed to be used anymore you will be prompted to use 12.4.8. No way around this, Apple has always done it this way. If you don't want to to lose 10.0.1 don't try and restore using your backup or any other method. Signed by Apple refers to Apple's process to check what version your phone is using and comparing it to what is available for download. During restore from backup your phone will send a request for iOS 10.0.1 to Apple servers and Apple checks what the latest and most secure version of iOS offered for your phone (12.4.8) and wont allow you to download anything else... When Apple comes out with a new version of software, the previous version is only available to downgrade to for a couple weeks then Apple doesn't allow it to be used anymore. In your case, 12.4.8 is the latest and last version offered for your phone as it cant use anything above iOS 12. Your stuck where you are, if you ever have to restore the phone for any issue you will be forced to 12.4.8 doesn't matter if you use a backup with 10.0.1 or not..