If you have been following recent posts in the hacking section you may have come across 2 instances where members of the forum have tried the "Erase All Content and Settings" option on a Jailbroken 4.3.3 device and the results have not been as expected. I promised to investigate a little further an report back, and this thread is the result!
Erase All Content and Settings
On a normal stock iPad, invoking this option by choosing Settings > General > Reset > Erase All Content and Settings, would normally wipe all of your content from the iPad and set it back to factory defaults. Occasionally useful, but if I am honest, I would normally just put a device into DFU mode and restore a nice fresh firmware if I wanted to achieve this kind of result. However, that is not what this post is about!
On a jailbroken device it has long been recognised that running this option will corrupt the OS and make the device inoperable, forcing you to have to put it into DFU mode and restore through iTunes. Normally you would therefore steer well clear of this option if you are jailbroken.
There was however one scenario where there was a clear benefit to using this option if you were jailbroken. If you had to hand your iPad back to Apple and for whatever reason you were unable to restore the device using a PC and iTunes yourself, you could choose "Erase all Content and Settings" on the iPad and hide the fact that you had been jailbroken from Apple, thus avoiding any argument about whether jailbreaking has voided your warranty. Because the device was rendered inoperable and a DFU restore would delete all traces of a jailbreak anyway, this was a reasonable solution to this one particular problem.
It appears that as of the most recent firmwares (I have confirmed myself on 4.3.3, but am assuming this is true of all 4.3.x firmwares) the "Erase all Content and Settings" option no longer works as expected. The device appears to start the process, a white apple with a progress bar appears for the briefest of moments, followed by a black screen with the traditional apple "spinner" which then sits there doing nothing until the battery exhausts or you reset the iPad by holding power and home for 10 seconds. One user has left the process running for 18 hours, so the problem is not timing. I left mine running for 15 minutes which is normally long enough for the process to complete.
Once the iPad is reset, it boots back into your jailbroken iOS with absolutely no changes from where you started. All of yours settings, apps, content, and most importantly jailbreak information is still intact. Therefore it seems as though the option has hung before it has started any of it's erasing process could start.
All jailbreak users should therefore be aware that there is no longer a way to hide your jailbroken status from Apple if you do not have access to a PC and iTunes with which to perform a restore. For 99% of users this is not a big deal. Most folks would normally connect their iPad to their PC in DFU mode and press the restore button anyway. BUT, for the small number of users that would run into the situation where they are returning their iPad to Apple and don't have access to a PC with iTunes, they need to take this into consideration. It would seem for them, the only solution is to wait and find a PC with iTunes that they can use.
I'd be interested to hear if anyone else can confirm or deny this scenario, particularly on firmwares other than 4.3.3 (I now have 3 confirmations for 4.3.3, so no need to further data unless you just want to try it out yourself)