Thanks for posting about it. I tried many if not all of the suggestions in this chain. What worked for me in the end was connecting to iTunes and doing the factory reset NOT via the settings in the iPad, but rather by selecting "restoring iPhone/iPad" within iTunes. This is found in the first box on the device summary page of iTunes once your device is connected - right corner next to the "check for update" button. I of course made a backup first (I chose to the computer). ALSO, iTunes will tell you, but you also have to turn off the "Find My iPhone/iPad" app before you can do this. You can turn this back on once reinstalled. It completely reset the system data for the device. I did have to set up the iPad as a new device without transferring data (TEMPORARILY) in order to update the software to the latest version. Then I did another factory reset using the iPad settings this time (under "General", "Transfer or Reset iPhone", "erase all content and settings". To be sure, I once again turned off "Find My iPhone/IPad" before doing the factory reset this way. In the end, system data was back to normal at factory reset levels. I turned back on the "Find my iPhone/iPad". Hope this helps!