iOS 11.4.1 USB Restricted Mode Consequences?

This just happened to my son's ipad. He added a passcode and it ended up locked and USB restricted. To fix it we had to hard reset it to factory default. Here are the steps - 1) plug the device into the computer with the lightning cable 2) [on the ipad] hold down the start button and side or top button continuously - until the plug into icon graphic appears. Note that you'll see the Apple logo first, keep holding it until you see a message to plug into itunes. At this point you can do a factory restore and then hopefully, restore a previous backup.

Here's a link to a helpful document: If you can't update or restore your iPhone, iPad, or iPod touch - Apple Support

That and other settings have no effect on either recovery mode or DFU. Recovery mode loads the normal iOS bootloader (iBoot) but does not load the operating system itself, so nothing in settings applies in recovery mode since the very code to implement settings isn’t running yet. DFU is even more basic and doesn’t even load iBoot - DFU can be used to recovery a device from any state since it allows direct re-writing of core firmware.

Other than hacking a device, which Apple does not support, there’s really no reason to ever use DFU and so Apple doesnt even really document it. For normal users running native iOS installs from Apple, recovery mode is all you’ll ever need to recover your device from worst case software and iOS issues.

(I beta tested iOS 11.4.1 and I can attest that recovery mode will still work as it always did).

I was about to answer, but then I thought about it and deleted my partially completed reply. You raise a really interesting point. Here's Apple's rather sketchy description of the feature: Using USB accessories with iOS 11.4.1 and later - Apple Support. It implies that the phone won't connect to a computer, which at first glance makes it seem like the phone will be dead forever. So I brought the subject up in the private forum for Level 6 and above users. The consensus is that you can still restore iOS using Recovery Mode, or, if not, DFU mode, as it bypasses iOS entirely and uses a primitive "bios" equivalent loader. We're pretty sure Apple has thought of that, but I'm hoping for further confirmation.

This really isn’t related to usb restricted. The process would be exactly the same before 11.4.1.

Having or not having a backup simply determines whether you’ll loose data or not. Recovery mode will always be the mechanism to reset a forgotten screen lock passcode. However, it also inherently erases the device to reset the passcode. Unless you have a backup, you’d then have to set your device up anew all over again and will loose the data you had.

If they don’t have a backup they would have to restore the phone as new. But that’s always been true.

Thanks, MB. See my thread in WC.