How can I recover an Android device after a factory reset?

Question

My two-year-old was playing with my (locked) Galaxy Nexus, and when she eventually handed it back to me, it was at the "Welcome" new phone setup screen.

Welcome screen

I'm guessing that she managed to hold down buttons and eventually end up at the factory reset option.

So I guess my first question is, was the phone definitely factory reset? Is there any other case in which the phone would boot up to this screen?

Second, assuming it was a factory reset, and I have never setup any backup software or anything like that, what are my options for recoving pictures and SMS messages?

I assume that my only real option is to somehow snapshot the raw disk device(s) onto my computer and from there run file recovery software on the image. Is that the case, or are there other options? If so, how do I copy the raw disk device(s)?

Thanks.

There are similar questions on this website under the tag [tag:data-recovery]. Have a look at them. — Firelord, May 15 '15 at 10:22

score 1 · Answer 1 · answered May 16 '15 at 10:12

1

Simply you can't. If you have made an nandroid backup, you can flash that one in recovery and you will get your data back

answered May 16 '15 at 10:12

TheRealProcyon

101
8

I'm not trying to follow you everywhere if you happen to misunderstand it for some reason, 2) your answer is partial and addresses only the title and not the rest of the question, 3) "Simply you can't" -- I find this to be a very bold claim. There are Q/A under [tag:data-recovery] tag. Please have a look on them. :-)

Firelord

May 16 '15 at 10:35

Sorry ;) I always learned you can't recover it. – TheRealProcyon May 16 '15 at 11:50

score 1 · Answer 2 · answered May 18 '15 at 11:19

After doing a little research, it looks like the basic theory is that you have to go through that initial Welcome screen up to a minimally-usable environment, then root the phone, then use adb from your desktop to get to a root shell on the running phone. From there, you have raw access to the memory devices, and can dd them off (onto an SD card, over the network, etc).

There are other, more complete guides to executing these steps, but if you have some basic unix knowledge, it should be sufficient to say root the phone and install adb on your desktop and go from there.

It would be nice if there were some kind of firmware-level utility to for copying the raw memory device, because using the phone so far as to finish the Welcome setup and root it will overwrite some of the data on the old filesystem, hurting the chance of making a full recovery. But it looks like this is the best that can be hoped for.

Anyway, after you've got your image file of the raw memory device, you can use other freely available data recovery tools to try to recover the previous filesystem contents.

And in case it's not obvious, next time set up backups!

How can I recover an Android device after a factory reset?

2 Answers2